The only dealing I've have with ones you clip onto the 12v battery were shite!
Had one on a compressor which is pretty good apart from having a compressor running every now and then.
Just bought a snap on battery one and it's the best thing I've ever bought
Wheel nuts, hub nuts anything not a problem!
And it has two batteries which last ages anyway.

Realy depends what u want it for realy?
Hth john