HAS, Sentinel, and the third one from here I’m forgetting. EDIT: Parsec is the third one I was thinking of!
Also, the mini-gun is fine, I missed the link!
Basically I'd say this from my perspective. I've only owned the HAS from these forums and it has been 100% perfect in every way. You will be hard pressed to find ANY threads or questions dealing with problems with the HAS (that's not user error).
That being said, the members on these boards are awesome, and SGs from them here seem to be great purchases as well. People on A-P who make and sell them (or provide plans for them like the mini-gun) do the circuitry correctly, build them correctly, and provide support if shit goes wrong. That's why I would stick to one of these.
Just do a quick Google search on the Windy Gaming one and the problems it had with that SCART switch and how they kept blaming the switch guy and never fixed their product.. not the kind of customer support you want. Also, it's like double the price... yeeesh..