I can't speak to the Qudratech winchs. I was a fan of the Smittybuilt XRC8s because of the low price. However, I burned 3 of them up now. One I burned out the solenoid and then the motor. The other two the motor went first. They have a one year parts warranty which comes in handy. If you buy one, be sure to buy it from some place like 4 Wheel Parts and get the extended warranty. It's well worth it.
I ended up buying a Warn 9.5XP new and picked up a Warn M8000 used off of here to replace the Smittybuilt XRC8s I kept burning up.