What's wrong with bluetooth in general? Essentially, it's an under-specified security nightmare. Of course, it's also pretty important for certain classes of devices.
I've never had a bluetooth device that actually worked reliably. Granted, my experience is limited to mostly keyboards and mice. If the bluetooth isn't giving me issues, the battery is. No thanks. I'll stick with USB and wired devices.
My Bluetooth headphones have been pretty bulletproof since I started using them a few years ago. Battery life still lasts two or three weeks ay my usage levels too. But I only keep them paired to one device, and I understand most of the grief with these sorts of things comes with switching between hosts often.