I listen several times several Grado models for several hours include their top models like GS 1000 or PS 1000. I think the best one are in quality to pricetag ratio notorially spoken SR 60 or SR 80. In USA, we can consider SR 225(i) or 325(is). When you love Grado sound, then RS1. GS 1000 or PS 1000 sounds „better“, because they are bigger or there are „better“ cables, well tunned, but there is nothing rational about their price tag. Serious addition in sound quality is not so significant as for other producers series. Grado models are perfectly tuned for several sorts of music, this is their great and unique addition. They are model to model tunned and different in several differences in sound purposes, but I can not consider the real value of PS 1000 in case when I can obtain HD 800, Beyer T1, or electrostats like STAX 404, or, especially with high end earbusters like JH 13 or JH 16 toys (especially with new amp) in same order of pricetag. Simply said, you obtain much more in sound quality with these models then with Grados.
All depends what you expect from them. When you absolutely prefer or love Grado sound then you personaly accept these disproportions in quality to price ratio and you purchase „better or best“ Grado models which does „superior in quality“ in compare with lower models like SR 60 or SR 80, but exclude interest on their pricetag. But when you rationally expect „the best“ quality or rational benefits from the model from the class of super high ends, then Grado will NOT deliver you the true super high end sound quality, especially when you see price tag and delivered sound reproduction quality. From headphones with price tag higher then 1000 dollars you simply expect much more then these grados can deliver you. Other models in this class like HD 800, T1, JH 13 or 16 .... delivers you much more.
The reason is the fact that Grado has one notorialy repeately used concept of conductor and he is not able do very serious innovation step or serious revolutionary discoveries. Him applied technology has rational limits which are hardly pushing able to higher levels of quality, when new innovation models like HD 800, T1, JH 13 or 16 with absolute new technological additions from latest discoveries, they open new possibilities to push forward the resulting quality of sound reproduction. So the latest concepts can deliver you more then 25 years repeated in common same technology tunned for this or this sound purpose or „form“ of headphones or for applied „materials“. So I simply say that Grado is limited in ranges of him concept of conductor and he is hardly able to do significant great jump in sound quality as was made by HD 800, T1, JH 13 or 16 with absolute new concepts. So this is the reason which forms from the worth to terrible quality of pricetag ratio for Grados. The situation is Europe where Grados are much more expensive as in USA only lights the problem.
When you see AKG K 701 and their very attractive pricetag then you can hardly find the reason to purchase GS 1000 or PS 1000 in their level of pricetag, especially in Europe, because K 701 are excellent product with extremely attractive price tag, but naturally, the sound reproduction and their form is the most important for true audiophile enthusiast by which you choose headphones. So when K 701 are not the sort for you (for your ears) than you can choose DT 880, Sennheiser models, T50, T1, HD 800 .... where the rationality of their pricetag is in real values incompare with several high level grados.
In the area of sound quality, simply said PS 1k are NOT comparing able with HD 800. I think, for me, HD 800 are class higher in quality then PS 1k. The mids or highs are much better for HD 800. The dynamics (balanced version) is much better for HD 800. The soundstage and airstage are absolutely uncomparing able (especially recabled with Voice cable). The voices for HD 800 are better then so spoken Grados. The smoothness between bass and middles or middles and highs are much better for HD 800 or T1 then Grados. For T1 you can very continuously listen the move from midds to highs, from bass to middles, when PS 1k or GS 1k are „hot“ for 80Hz frequences and discontinued. HD 800 are very analytical (clinically) but their detail is excellent, incomparing able with grados. When you listen the track where the sound came continuously from bass spectrum (by different Instruments) to middles and then to highs, then you will see how false are highs for GS 1000 or PS 1000, or where are problems in dynamics for them. The T1 are simply said incomparing able with grados in this aspect. Instruments localization is much better for HD 800. Bass or trebles is specific thing for HD 800, there was written million of replies or posts about it, but there is the question what you compare with what thing. When you apply Stefan Audio Art Voice cable for HD 800, balanced version, then you obtain much more in bass or trebles as with stock cable. So when you apply balanced amps like Rudistor’s, Woo audio, Ray samuels or Eddie Current, then you obtain better quality from HD 800 then from Grados in most aspects of sound quality or reproduction.
I think, Grado PS 1000 are heavily absurdly overcoted and this is their reason whay they are not „legendary“ in opinion as HD 800 or T1 owners. This is true for USA customers and dramaticly for European one. I do not know what is all different between GS 1000 and PS 1000, but 70 percent higher pricetag is absurde. What is different in production costs between RA1 (or SR 225i) and GS 1000 or SR 325i(s) and PS 1000? Only bigger size means much bigger pricetag? Yes, each model is individually tunned, tested, paired, sorted ..., but this is true for HD 800, T1, JH 13 or 16 too. When HD 800 or T1 are absolutely new inovation headphones with absolutely new Technologies, the development took at about 5 years, Grado models are in common in same principle during last 25 years. When today HD 800 are slowly going down with pricetag, GS 1000 costs same 995 dolars as in time when released, three years ago. Is th production so expensive so there is no space for reducing the price? Has Grado so intensive development so he is not able to reduce the price in fact of costs of made thier development? HD 800 has very intensive long term development so when I purchase one I pay the cost of development distributed between sold models. As Sennheiser sell more and more items, he is able discalculate the value and reduce the final pricetag for HD 800. But this aspect I can not see for Grado models, for example for GS 1000(i). I think they are simply truely overcosted. As higher (bigger) Grado model the overcosting is higher and higher. And naturally, when we speak about Grado amp, I think, there was said a lot of info in this forums too. When for HD 800 you obtain much more fun during listening trough different sorts of amps, with Grado models it is much more complicated. Some gives benefits for them but some are without good listening experience.
In the end of my reply, simply said all depends on answer for one simple question, what you expect from sound reproduction, from headphones listening. When you strongly love grado style sound and you own lower models like SR 60, SR 80 up to SR 325i(s) and you are very happy with them, then you can find motivation to purchase RS1 or GS 1k or PS 1k to obtain superior sound quality from loved lower models and you absolutely not see or accept their rationality of pricetag. As higher model the ratio is worth and worth. When you want obtain from the class of super high end headphones excellent and „actual best“ sound quality, you want invest to serious and rational product, when you want something where you can truely argue the investment to them for your wife, then Grados are nothing for you. The HD 800, T1, JH 13 or 16 and other headphones delivers you much more in sound quality with adequate (rational) pricetag. When you want generally better sound quality, better in most of aspects of sound quality, then models like HD 800 or T1 delivers you much more. The Grados has excellent this aspect or this aspect of sound reproduction, but there are several other one where they are much worth then these top headphones, so the highs are less quality as T1 etc. So there are the aspects for GS 1000(i) or PS 1000 which are less sound quality as is rationaly expected from the class of super high ends. All depends on your decision, nothing less nothing more if you want invest to them or not, if you want superior sound quality for complete Grado production of headphones or not, if you want rational price tag headphones from (super) high end class or not, nothing less nothing more.
PS: All what I presented in this reply is only my personal opinion and experience which I found during several hours of listening trough Grado models and other models like HD 800, T1, D 7000 etc. I am in opinion neutral and objective, so I am not narrowed again or for somebody or something.