An answer for those looking for a"freestyle" mode...

[Kevhouse]

I was looking on the Codejunkies website today, and here's what I found.

http://us.codejunkies.com/search/codes/Rockband_Action-Replay-MAX_13634118-13___.aspx

There are codes on there for never failing (and one made especially for the vocalist). Grab yourself an AR and you're good to go....

[dady5000]

Cheating in MY ROCK BAND? oh wait... HMX's ROCK BAND!!!!!!!!

[Parodygm]

Probably of limited help. I'm not sure what percentage of Rock Band sales are on PS2...

[killer_roach]

Last I heard, about 2% of Rock Band owners were on PS2, so yeah, not a whole lot of help.