Yes, the 900 is rootable, at the cost of a tripped knox flag. I've had mine since about a month after it was released, and I really like it. I purchased the Logitech bluetooth keyboard and it has been really good so far. Out of the box, the tablet is great, but if you root, install TWRP and flash the new debloated ROM, the device becomes significantly better. Lag pretty much disappears, boot times are vastly better, and so on. I'd suggest looking into Xposed for additional tweaks for your device as well. I've not experienced the wifi dropouts ( and I think there may be a new xposed module out there for it... do a little searching and you'll find it ) on my device, either pre or post root. Battery drain doesn't seem any worse than any other tablet I've ever owned, but I control what's running with boot manager, and I kill wifi and BT when I know it's going to sit unused for a while.
