The Google Experience phone is an i9505. Personally I recommend you buy one of these, either a normal one or Google Edition, because it means you don't have to bother with bootloader hacking and you don't have to worry about playing cat and mouse with carriers. Plus it'll be network unlocked and won't come with AT&T's bloatware and branding.
Thanks for all your answers.
I'd love to go ahead and get an unlocked i9505, but budget will not support. I can swing a subsidized phone from AT&T right now...especially thanks to the $100 they'll give me for my old iPhone 3GS (I'm keeping the 4S as a backup for now), but $600 or whatever for an unlocked is not possible at the moment.