Looks like a Wilton Shop King without the pipe jaws on it. However, the one that I have says Wilton on one side and Shop King on the other. If yours does not then perhaps it's a knock-off.
It would stand up to medium use. It was made for the home mechanic, not a factory. It is not an enclosed/shielded slide so grinding is a no no and the lead screw is vulnerable.
$20 isn't too bad of a price either. don't forget to factor in shipping however. Like mjozefow said, it's a medium duty vise. If a vise breaks it's most likely the users fault from expecting to much of it or using it improperly...