Yeah, I've read about people trying to hack various Qi receivers to work inside the OPO, but the hacks look too hackish at this point, and results seem mixed at best from a quick read of the OnePlus forums. A couple reviews of the external micro-USB ones say it works okay with the OPO, but I'm worried that I might have some difficulty finding a case that protects the ribbon cable connector enough.

The OPO really does seem like a great value, though, so if I can find something that works and isn't too bulky, it's probably the way to go.