I've got several of these through my boat, and they seem fine for low current uses. Problems come when you start asking them to pass 10 amps or so (120 Watts) - they're definitely not happy at that kind of load. An inverter of 150 W or greater should definitely be hard wired. I'm not aware of any 12V connectors for higher current rating. There are household connectors rated for 15 or 20 amps, but these are all for 120VAC service - I hate to think of the confusion that would be caused by trying to use them for 12VDC.