Bad news for people who can't wear bowls because of the comfort. Although I have a strong suspicion it might be a great candidate for a "1000" mod (distancers and bagel pads).
It's good news in disguise. Necessity is the mother of invention by changing the cost relationship between playing it safe and going for broke. Nobody would ever think of altering the beloved RS1 - or, for that matter, the wonderful HF2. But what if you could bridge the gap between your used RS1 and the $1,700 PS1000 by making changes that amount to the cost of purchasing jumbo pads? Take what I'm saying with a pinch of salt, since we're working without a net - or aluminum. Still, you can match the HF extension of the GS1000 by swapping pads. You can also recover the bass you'll lose by venting the drivers more fully. Without the hammerhead ring of the GS1000, you may be able to do this without ending up with the huge bass spike of the GS1000. If not, the next best thing is to jettison the secondary mahogany shell and stick with the first-stage underpants. Cutting the wood cuts back on the bass spike. The result is an RS1 you can wear with jumbo pads, which is what the PS1000 was intended to achieve.
I haven't done this. I sold my RS1s before Grado came out with the PS1000. I don't need to buy an RS1 to achieve this effect because I have access to mahogany, allowing me to build my own first-stage shells. It's cheaper for me to buy jumbos than it is to buy an RS1 and jumbos - just to prove a point. But somebody out there is going to read this and go for broke. Somebody is going to take the Bilavideo challenge. Whoever does it first, just know that you owe me a two-liter of cream soda (A&W if you please). What you'll end up with will not look as nice as a PS1000 - with those beautiful anodized aluminum shells - but it'll give you an RS1 fit for jumbos, which is what the PS1000 is all about.
Before I got my hands on mahogany, I was doing the next best thing with plastic. My SR60s with jumbos were sibilance free - and they had slam. They didn't have quite as much slam as a PS1000, but what do you expect from plastic? The point is, it got so close I ended up selling my PS1000s. I love those shiny shells but soundwise, I have no regrets.
Whoever has the guts to give it a try will find out. Happy days, boys. Happy days.