I've decided to be patient and do an extended test run. Mal's advice (thanks!) inspired me to actually give the sr60i's (actually it was an sr80i) a try; I was very fortunate to be able to find an owner right here in my campus!! (through university forums, super n-eat)
He, unfortunately, only had the stock flats and I wasn't crazy enough to suggest carving a hole in both pads to mod his grados, haha. Still, it was great meeting another audiophile, and we exchanged headphones for the week: his grado sr80i for my denon d2000.
Here are my initial impressions of the sr80i compared to my existing 'phones. [DISCLAIMER: I've only had the sr80i's for less than half a day]
vs AKG K702:
The sr80i made a bad first impression with its much-reduced soundstage compared to the K702. It's not the fairest of comparisons I suppose but it's the first thing I noticed. In some ways, I disagree with the oft-repeated idea that grados tend to place you in the front row seat set; in my opinion, it was more like the entire theater shrunk so naturally, I ended up being closer to the performance.. However, I agree that the grado sound is the antithesis to the cold, clinical, and simply stonefaced K70X, the sr80i sounds very lively, very aggressive.
vs Beyerdynamic DT990-600:
TUBE HUMMMMMMMM. Also, the treble of the sr80i is so much tamer. I've read numerous complaints about the supposed harshness of the prestige series, and all I can say (at least for the sr80i) is, it's simply sounds not veiled to me. Strangely, it also feels more fatiguing than the dt990, which is my most fatiguing headphone yet, both sonic and headband wise.. and yeah, the complaint was for both of them- must be because the driver is so close to the ear. Finally, I AB'ed both phones and came away with the conclusion that although the sr80i is the more energetic of the two, the dt990 is simply more engaging, more musical. Mental burn-in?
vs Denon AH-D2000:
The d2000s are pillows. The sr80i feel like.. um.. slightly-yet-indescribably uncomfortable on ear. And it's not the foam or the headband simply being stiff and new, because this pair is totally used. Maybe I just have to get used to it. Er, sonically I think the sr80i is superior to the d2000 with the sole exception of clarity.. and maybe soundstage. I think the sr80i wins in soundstage though, because it can at least pretend to get you closer to the stage, the d2000 feels mid-fi in this regard in that it just "flattens" a good deal of distance and separation. Even in fun-ness I prefer the sr80i. The d2000 can do two things that the sr80i can't though: protect my ears from the winter cold and keep the librarian from catapulting encyclopedias at me due to headphone sound leak.
vs Sennheiser HD650:
Runner up for grado antithesis, due to its mature, laid-back nature. I think that title would fit the hd600s better though, as the hd650 still has that fun factor in, but in a much more refined way compared to the sr80i. Sound quality wise, and this is the first time this is coming out of my mouth, the difference is Night and day. Day and night. The sr80i is not unlistenable in any way, just that compared to the former's smoothness (something this grado doesn't have, not one bit) and.. plainly stated, euphony, the sr80i suffers a one hit KO. A saving grace from this comparison could be that the HD650's bass feels a little bit excessive at times to me but the grado's is just right, cuddled snugly up in my perfect zone.
I'm assuming the sr225i and the sr325is will give me a similar-enough experience.. (i.e. passive listening) There are no stores that I know of within a.. ~50km(?) distance that have grados for test drive. The most popular headphones here (Hangzhou, China) currently seem to be the noise cancelling Beats, the k701, hd598, dt880, and tons and tons of Audio Technicas, especially ath-ad900 and below.