There is not that much that can go wrong with these devices, but they are a bit on the heavy side.
I bought one of these cheap eBay devices some time back and they definitely do the job. As an example, I helped Gait rotate his wheels when he came to visit a few months back. On one of his wheels the nuts were very resistive to undoing, even with a 5 foot extension bar on the end of the breaker bar. I then used the torque multiplier and with very minimal effort those nuts were undone.
My only advice with these cheap eBay units is to disassemble them and to repack with good quality, high pressure grease. My device had very little grease in it when delivered and it did not feel smooth when turning the drive lug. After a rebuild it works as I expected it should. A useful tool to have in the cupboard.