Most of the feedback I've heard from people who have used both the Vanguard and the G155 is that the Vanguard has both a higher-quality screen (specifically in regards to viewing angles) and a much better pair of speakers than the G155. Oh, and let's not forget the Halo stickers, which are...
Gaems' Halo-themed Vanguard PGE setup is $50 off at Amazon. Usually $350. Not sure if this is a limited-time sale or if it's a general price drop, but it's the lowest I've seen it...
I'll be headed to Circuit City to grab my cousin a $10 copy of Conan for the 360; then it'll be off to Best Buy to grab a $25 copy of GH: Aerosmith (Wii) for my father-in-law... while I'm there, I just may grab myself a cheap copy of Turok for the 360. Wo0o0!!!
I'd like to track down a few PS2 RPG's I missed:
Persona 3
Shin Megami Tensei Nocturne
The Digital Devil Saga games
Really make that $100 go the distance; the most (or rather, longest) bang for the digital buck kinda thing.