cm7 is still only beta but some of the releases are still very well finished. However for someone who isn't going to be updating all the time I recommend miui. The newest release is fast and feature rich with very very few errors. Just make sure you are careful when you get install. Miui.us has the newest downloads. Good luck
I would use MIUI every day, except the battery life was significantly worse. Maybe this has been fixed in newer versions. But I do love the amount of customization options with MIUI.