I ordered the PASS stuff and it has some good info, but honestly, I never ever really used any of it once in class since they gave us all the materials to study.

Helpful before class, but will probably not use them once your there. Might be good for a PC later on down the road though.

The only thing that I bought that I recommend is the 737 Cockpit Companion (SWA Version). The two FRM manuals you get in class are huge, but not required to be carried in your flightbag. The CC is a mini version that alot do have in their bag. It has some great information. I think they are 40 bucks or something around there.