I don't know much about the heads, but I do know this: I have a Pro Comp distributor (made in Australia, not China) and...well, you get what you pay for. I also know that the company was sued by MSD for ripping of their design.
I've heard a few bad things about the heads (which I believe are made in China), but I don't have any first-hand experience. If you decide to buy a set, you'll pro'ly have to spend some money getting them right. But if you do the math, they may still be a deal.
If you're going to go Chinese, you may consider the 440 Source heads (NOT trying to ). The Edelbrock heads and the cast iron Indy SRs aren't much more money, and you may want to go that direction.
Good luck on the build.