Has anyone seen or used one of these

They are cheap. I wonder if they have issues?

Chinese made for one, but speedmaster seems to have their stuff at least somewhat together. Their eddy knockoff heads seem like a really good deal. Their Airgap knockoff is decent, the casting is good but apparently the ports aren't as great as the real deal. I have one of those already that I've modified for fuel injectors but I'd like to try a single plane and the only game in town without modifications is the eddy efi super vic and that's $550 USD which hurts.