So far, it's the most crash-prone application I've ever used on my Mac. It is literally unsable - not because of the missing functionality, but because it crashes constantly!
I have virtually brand-new iMac with max memory, max hard drive and the fastest processor. I have uninstalled and re-installed. I have done every update, run every disk utility, etc. It's still a disaster.
Here is just a sampling of the crash-tastic mess:
1. Add a title: the moment I begin to edit the text it crashes
2. Add an effect and click play: it crashes
3. The Inspector is hit or miss: sometimes it shows properties, sometimes it doesn't. Changing a property causes random crashes
4. The auto-save, well, doesn't. It loses MOST things without saving
5. Projects and Events both mysteriously vanish
Because I started with iMovie (I struggled through the old FCP), I actually like the FCPX. It's intuitive to me. I understand the frustration of pro features that are missing, but if the application is too unstable to even use, I'll never have the chance to find out!
Keeping my fingers crossed that they fix it. I want to like it.