> Does the ANR on the Telex 850 get powered on the 737, since it needs a hot mic for power
Yes, at least in the -300 & up. There IS hot mic going to the CVR, just not to the other pilot, so the mic DOES have power all the time. I think some of the -200's may have caused difficulty with that setup, but the newer jets don't seem to have any issues.
I will, however, second the QC2 + UFlyMike setup... works great, and by all reports, better than the Telex for most people. Plus, you have the QC2 for music & quiet while commutting or deadheading in the back.