I am thrilled with my well burned in 325is's and ALO the Island! I was at TAVES here in Toronto and heard all of the Grado
line, and if I had to upgrade would personally get 500e - similar to my 325 is but more spread out sound stage - yet
I love my 325is and feel no need to upgrade...same with the Island. Magical combination with Pure Music on my Macbook Pro Retina!
BTW, getting the best sound for yourself isn't always about spending the most....just getting the best synergy for your taste.
+1