Doug, I can only tell you what my experience has been. I have a Holley Dominator ECU. I went with the Dominator because I wanted to use dual O2 sensors without an add-on module and I wanted the capability of blending both types of EFI logic; speed density and Alpha-N. I also wanted flexibility in what I used to generate the cam sync. and crank signals. I didn't really care whether Holley's tech support was any good but I wanted to buy an ECU that was manufactured by a substantial company, that was likely to still be in business in ten years. That being said, the proof is in the pudding and I'm happy to report that my EFI system works better than I ever expected it to.
I've attached a video taken out of the rear window of my Pantera. Turn your volume up! Notice how little throttle it takes to get the car moving along. Also notice how smooth the idle is. I have a solid roller cam and you can roll a golf ball through my mufflers but you'd never know it because EFI smooths the motor completely. I'm not sure everyone would think that's a good thing but I do!
