At least I still have Battlefront II on the PC.
The main problem is the controls. They suck. (I gave the game a "hard" difficulty because it's hard to function with the controls.) You can't move your aimer up w/out locking on or zooming in. Your gun fires really slow. Also the graphics aren't that good. The main thing that makes the PSP so great is that it has better graphics than any other portable system, but I've played DS games w/ equal or better graphics. (Mario 64 DS for one)
The whole customization thing is pretty cool I guess, although it does take forever.
Customization, new heros, hero CTF, and the new maps are the only good things about this game. I would actually enjoy this game if the controls weren't so annoying. If the PSP had a second analog stick thing it would make it a whole lot easier. I guess they just ran out of buttons.
If you still want to try the game, please at least rent it first. If not, buy it used. And keep the receipt.