Got the latest version of multiman installed (v1.13.04 I believe) and no problems so far. My backups are working great (tried Fifa11, Fallout New Vegas and GT5). I've also kept the lv2 pkg just in case.
Thing I'm loving the most is the snes emulator (SNES9x) and can't wait for an N64 emulator too!
I'm quite new to this scene too so I didn't really know where to start. I started with geohots jailbreak I then moved to Wutangrza 3.55 cfw + geohot and now I'm running kmeaw's 3.55 prepatched pup on an old launch 60gb and so far its working great.