Never heard of them before your post. As previously noted...stick with a mfg with a proven track record (especially for a $250 BCG).
While I understand not wanting to pay through the nose for a simple BCG, there are plenty of carrier groups out there now for prices not far off the $250 ones you are looking at on GB. Check in on the BARFCOM EE. There are multiple, mil-spec, quality carrier groups from reputable mfgs just on the first page of the new, upper receivers/parts section alone for similar prices as to what you are looking at paying for a no-name. Buy once...cry once!