I did the Sniper 2300 and the RobbMc Powersurge as well. I have been running it as my dd since August. I want to convert over to the Hyperspark, but so far it starts and runs so well that I keep putting it off.
When I first back out of the driveway in the AM, if I rev it up too much and then hit the brakes, it will stall out. I bet that better timing control would eliminate this. Once it's warmed up after a few minutes, it won't stall under the same conditions.
So I may well be shortchanging myself on better performance or fuel economy, but it is a new car compared to how it was before EFI.
1990 Grand Wagoneer with HD towing package -- everything works! (for now...)