AC12 can be downloaded and run in demo mode so you can have a look through the AC12 library as much as you like.
I wouldn't really rate the AC library as a factor in deciding wether to upgrade .. if you do you are bound to be dissappointed! Multi-processor support is well worth it however (maybe not on small jobs)
cheers,
Owen Sharp
Design Technology Manager
fjmt | francis-jones morehen thorp
iMac 27" i7 2.93Ghz | 32GB RAM | OS 10.10 | Since AC5