I used Final Cut Express for a few years, and held off on FCPX until last month when I talked to one of the video guys at my local Apple Store. He said FCPX is so much faster that FCE, and imported so much better, there is no contest, so I went for it and bought 10.0.8.
It took a few tries to get past the awkward starting procedures, but once I got to editing, wow, what an amazing difference. I used to hesitate every time I thought about tweaking a project I was doing in FCE, but I jump right in and fly through changes in FCPX. I'm fully sold on it and won't look back.