I haven't tried CM7 yet on my Atrix.I have it on my Incredible and it's amazing but my fingerprint scanner and Web-top are things I use daily so I can't really rock CM7 until its ready.
But...I keep hearing people on XDA say it's very good and mostly functional so if you're not affriad to give up the above features go and download the ROM and make sure youre using the ROM manager cwm or ROM Racer's version either will work and back up your stuff cause it does a full wipe.