The songs are Rockband 2 are much better to my ears. I am use to Rockbands style of guitar and i find it's more easy to use. It also looks and feels more realistic. Going back to guitar hero controller the hand pains come back. For the question Rockband 2 or GHWT? It's not the peripherals you should be looking at it should be the game and set list of songs.
I can confirm Guitar hero 3 controller working in Rockband 1.
BTW What really sucks is that the game luanches with DLC??? That's so bullshit,it would fit on the disc….. they just want more money,greedy basterds. That's why i use one acount with a few people and only get songs on one account and everyone leeches.