Big Manual--Steep Learning Curve
Too late for you probably, but for others considering purchase FCE 4, give serious consideration to the level of commitment necessary to understand and master this program. The manual is so g.d. long because FCE 4 is a complex and complicated app. A "Cliff Notes" version simply wouldn't be helpful given the level of detail necessary to use this powerful app. I found the manual better than most and STILL became frustrated to the point of scrapping attempts to use FCE.
Here's my advice for those uninitiated to the world of video editing: Your experience with iMovie has little bearing on the ease from which you can switch to FCE 4, despite the professional reviews of FCE found online (macworld, for one). For those considering switching, here's a quick test to help you decide. 1. Know what a "scratch disk" is? 2. Do you have 20 or 30 hours to learn a new app or do you have a friend/relative that can tutor you? If you answered yes to both, definitely purchase FCE. If not, I suggest learning to live with iMovie's limitations.
I switched from iMovie HD to FCE 4 b/c I heard iMovie 08 was a stinky pile of poop relative to iMovie HD, which I had mastered. Now that iMovie 09 has received rave reviews (again, Macworld), I'll be purchasing that and selling FCE.