I had started another thread about my current Prestige comparison with different cushions, but judging by the activity, I should've just posted here. Seems a lot busier!
I've been comparing my brand new SR225e, my recently-serviced SR125 (which I could swear came back with a thicker cable), and my original SR60. I've been using G pads, L pads, and S pads (all genuine Grado), as well as some Geekria pads that are like S pads with a hole (essentially a pre-fab quarter mod from Amazon).
Everyone's tastes and hearing are different, of course, and I should probably add a disclaimer in my signature that mentions that I have some hearing loss, but I think my favorites are the S pads across all three headphones.
G pads: I guess it's the wider soundstage brought about by the distance of the drivers from the ears, but they sound a bit "artificially cavernous" to me when going back and forth with the others. They're also a bit too bright with the SR60 for me.
L pads: Less comfortable and also just a bit too bright for me, I think. I can tolerate them, but they're probably not my first choice.
S pads: For me this seems like the sweet spot. They tame the brightness a bit without losing much detail (if any) while bringing in some fun low-end (although I'm not a bass head). They're also reasonably comfortable.
Geekria: Maybe these compress more, but they seem to bring in even more low end, so much so that I think they're just a bit "boomy" sounding. Some might like it, but I think I like the S pads better.
I would note, though, that I could probably listen to any of these combinations pretty happily, maybe with the exception of the G or L cushions on the SR60, which I think are just a bit too harsh. Differences I'm noticing are not as apparent when I'm not going back and forth between models and cushions in a short time.
Interestingly, I also think that the changes in cushions make a bigger difference than changes in models, at least between the SR125 and SR225e. Even the SR60 really doesn't sound very different to me, which I think says a lot about the quality of Grado's entry level, even when the headphones have aged 15-20 years. My SR125 should be about 21 years old now, although I'm not sure what all was done to service them and which parts might be new....