Just got the GP3U. Bottom line, it's terrific for everything. I'm mainly using it for PC and Console gaming, but it also looks great with HDTV and Blu-Ray (at 24fps). Games like Bioshock, Crysis, Witcher look incredible. I have nothing but good things to say at this point.
I haven't tried the attached speakers yet, and probably won't ever need them.
A huge step up from my 2407 Dell for PC use, and very comparable in image quality to my Samsung LNT4061F.