I am sure it would be serviceable and worth it at 90 dollars. I mean, 90 bucks? It is worth a shot in my book if you need a frame. I would put cheap yet durable parts on it and treat it like a red headed stepchild. I would get a rigid fork for it (not the Nashbar one, go
surly). I would crash it into trees.
Please don't compare it to a Gunnar frame that was handbuilt in the USA out of superior steel.
Of course it is cheaper. It is made out of 4130 . It was welded by drunken midgets in a factory in taiwan. It will be heavier and ride like a tank. I have a bike (surly 1x1) made out of 4130 Cromo welded by drunken midgets in a factory in taiwan. It is heavy and rides like a tank. Good for what it is good for. Beating the hell out of and not worrying about.
I don't expect it to ride like my gunnar and it doesn't.
As long as your expectations are proper in that you are not going to be getting a great steel frame I would say go for it. you will be getting a heavy steel frame capable of taking a beating while also delivering some of the benefits of steel.