They are from the exact same family as the infamous Broadway Photo. If you don't know who Broadway Photo was, just Google "Broadway Photo Scam" and you'll get a feel for their background.
As for what BigValue Inc does now, they primarily advertise US versions of the item they are selling and then you end up with a Grey Market camera or lens. A good portion of the time, you get everything that's supposed to come with the camera (or lens)...but sometimes you're missing things that are somewhat critical, such as a battery, battery charger, eye-piece, etc. And then when you raise questions or try to return the item, you start getting the run-around and it take s a long time to get a refund or you may not get all of your money back after they take out a phantom restocking fee.
There has also been a few times where they send you used gear, although that doesn't seem to be as prevalent as the Grey Market scheme.
Buyer beware! If you choose to buy from them, you're not getting what you're paying for and you're taking a significant risk.