generally they're not terribly high maintenance, but anything compared to a nexus is high lol. Also, had you gotten the developer version it wouldn't be high maintenance either. The maintenance comes from the carrier lock and having to bypass it. not trying to flame, but if you didn't purchase the dev edition or the GPe version then you bear the risk. Then either way, htc states that by unlocking you waive your right to your warranty. Again, not being a jerk or trying to be mean, but next time I would take at least a few hours to test basic functions before jumping into it. If you already had and it was working fine before, something must have went wrong during the unlock/root process. Either way, let's just hope an RUU drops before your R/E runs out. You'll still have your warranty but we all know the potential risks of getting a "like-new replacement".
p.s. i would still try a new sim. over time heat can wear away the laminated coating on the sim where it touches the contacts on the inside of the phone. It's an outside shot and might not help at all but it would definitely be a more feasible option to try at the moment.
Last edited by pokedroid; 6th April 2014 at 06:20 PM.
Reason: adding suggestion