I'm trying to get to the sprint rom, to get the updated radio firmware, then go to a custom rom, so that data works, but to make that last move requires root

poot didn't work on a freshly installed ZVF for me. Poot did work when i went back to VM rom.
Based on what happened after the sprint rom update i have a feeling it just blows away your data anyway and a custom rom wont work because I had to use the virgin rom and do the MSL reset. I think I'll just ask for the HTC when I talk to my escalation lady (FCC complaint) tomorrow. This phone is just destined to be a pile in various cities. I've been troubleshooting with them over a month and the gremlins in virgin engineering must have an "easy button" that does nothing it seems they just say "we fixed it, try again".
then you say 2g/3g still toggles, and they say ok i'll send back to engineering, 48-72 hour wait.
repeat.
repeat.
repeat.