Same here - no problems at all and had it since it was first available in the UK. All updates well well and the hardware is mostly holding up nicely. I say mostly because the fingerprint-reader has become rather inconsistent and so I usually use PIN unlock instead.
I have 2 friends with the Atrix also (they copied me!) and only one had a couple of problems, which we put down to the gingerbread update not applying properly. We did a clean boot using the recovery menu and ever since then it has been fault-free.