I've used Pro Comp stuff, but honestly the more items and pieces a component has.... the greater the chance of it being screwed up.
Chinese intakes. A lot of them sold. Very simple in construction with few things to go wrong. Little rough out of the box.... but very easy to clean up with a die grinder and carbide burr.
Chinese heads. I've personally ported and used a set of 175cc heads on my 1990 F150. Port design isn't too bad. Really rough out of the box, but they ended flowing 267 cfm on my bench out of an actual 165 cc. Push rod hole locations at the top aren't exactly right, leading to a small amount of rubbing as the hardened steel pushrods made their own clearance in the softer aluminum.
Electronics? Ouch. Too many components for my liking. I'd like to use flashlights as a comparison. I buy a cheap Harbor Freight LED flashlight for $6. It lasts 3 weeks. I buy a nice American LED flashlight at WalMart for $20. It lasts 3 years... See what I mean?
MSD distributors are so good because of how easily adjustable the timing curve is. The 6AL boxes are used by NASCAR. I own 4 of 'em. Any probs, I send them back to MSD and $35 later, I basically have a new box.
Look on Ebay for MSD deals. Even if you buy a broke 6AL box for $50, you send it off to MSD and you have a new box for $90.
Just my experience.