What's the deal?

Found this goodie on ebay while wasting some time, caught my eye. I've read the specs, and have come up with that it's a car controller, so what's the drawback? I mean, what is the difference between one of these and a MGM 80a, aside from the 20a less and $50 price tag? I'd be willing to try one out with a Feigao 380C-7T in my T2 to replace my Lehner 5300/7018 system that's showing its age, maybe even use it with a bigger motor if I know it'd be okay......even at $50, I'd rather not waste it on something I'll just throw away.

I also remember seeing 80a ones a while ago, can't really find those now, would they be any better?