Good day Francesco, its been a while indeed, think 2008 or something?, but maybe I am mistaking...
Anyway, good to see you around again, enjoying the greatest headphones ever made. To me, at least at this point, PS1000 are the best Grado, because John managed to combine many things in one and made it possible for having just one pair of headphones that do a lot of things at high level. Like you mentioned already, PS1 are fantastic, but their use with several genres was pretty limited for my taste. I wrote about this many years ago, especially when their price become simply crazy, which made them a dream headphones for most folks only. Personally, I choose GS1000 over PS1 at some point, which will be not accepted by many, but I dont care, because its still the matter of preferences anyway.
After many years in this hobby, I believe in one thing only and thats synergy. I have heard many headphones, include almost all Grado's, and only few keep their value up to date, some got very expensive, some just still keeping their own place after many years, even with so many new products around, where PS1 and HP1000 are very good example of that for sure.
As for the new headphones that may be interesting to try, I am not sure, because after I tried Koss KSC75 from out of Cary CAD 300sei, my mind just explode and I kind of lost my interest for anything else, however still want to try PS1000 with my Cary one day, cos GS1000 sounds fantastic true it.
Ah, I dont know what the hell I am talking about, guess just glad to see you around again