I've had nothing but good luck with mine, but I've only had it a few weeks. I haven't seen any reboots, data drops or any of the other common complaints with the Bionic, possibly because mine came with 902, which seems to have fixed most of the problems.
Battery life leaves something to be desired, but coming from the Tbolt and the Charge you'll be used to the battery life of a 4G phone. I use Tasker to keep BT, GPS and Wifi off when I don't need them and that helps a lot, but I still carry a spare charged battery with me.
One thing I do want to get is a Belkin 2.1 amp car charger, my standard 850 mah charger has trouble keeping up when I'm navigating and running a podcast or music though BT at the same time.
If you're looking for a good sturdy case (I'm hard on stuff), the Trident Aegis case is really excellent, I got mine from Amazon for $10. It adds bulk, but it really fits nice and protects the phone well.
I'm not a big fan of the stock car mounts, I drive an old Jeep and need something sturdier, so I've got a Ram mount with the X Grip device holder, works fine with the phone in the case or out, or with the stock battery or the 4000 mah battery. I've never had it come out.
I've rooted mine to get rid of the bloat and block some in app ads, but it worked fine without it. I also like to try alternate ROMs so rooting was a necessary evil for me.