I have the Grado 325 and Alessandro MS1 (a modified Grado 80--but often compared with the 125 or 225)--both bought no later than December 2011. Like Mal, I don't consider them to be my go to every day can(s).
Everyone has a different comfort factor. For me the regular Grado/Alessandro ear pads took some getting used to, but--along with the head and etc.--are fine for 2 to 3 hours of listening. They don't have Beyer, AKG Q701 or Senn HD 598 comfort, but they are OK.
I hear noticeably better clarity and bass from my 325 than from my MS1. The highs on the 325 are quite bright; some call them harsh. However, I have found that playing them through my HiFi Man EF2A (once it burned in--it was awful at first) the highs lost that "just south of the edge between very bright and harsh. It's a great sounding can for rock, blues, country--and probably more genres.
I haven't heard the RS line yet, but the 325 (and probably the MS2--based on the 325) is a nice place to be in the Grado line--especially with the right amp.
Base on what I have heard on my MS1--the 80 is probably a good place in the line to stick you toe to determine if they are for you. On the other hand, if you have the means, the 225 has oft been reported as the sweet and most popular upgrade spot in the Grado line. Your money --your choice.
Edited by KG Jag - 4/25/12 at 3:44pm