Many resales of the Holley (Sniper) & other aftermarket Fuel Injection Systems

I'll go along 100% that most resales are operator error. That said, these people who make all this stuff need to make it less complicated so people with average intelligence and understanding can have a better chance at success. Some of the wiring and instructions are devilishly complicated and that point cannot be argued.
Trust me, it's really not that complicated. If you've ever wired an MSD into a Chrysler product you're halfway there. Yes, you have to figure out stuff like how to get ignition-switched power to the components but if you can understand that concept then it's just another job.

Here's an example of how this scenario plays out. In the instructions they beat you over the head with the idea that the main ECU power and ground wires must go directly to the battery. They don't say it directly but it's because the ECU is susceptible to RFI which can wreak havoc on it. For 99% of the people out there doing this, the battery is basically the only place in the entire car that provides 'clean' power. It's a flaw in the product for sure but if you understand an accept it as fact and are willing to work around it, it's not a problem.

They real reason they beat you over the head with running the wires to the battery thing is because guys A) think they know better than a computer and B) are lazy because they will find ANYWHERE BUT the battery to put the main ECU power. They'll wrap bare copper wire strands around the coil + lug or shove the wire into the voltage regulator connector which invariably will cause problems. They call the tech line when the ECU keeps resetting itself or something and that's the first question the Holley guy will ask - did you run your main power to the battery? No? Sorry, can't help you. Guy hangs up frustrated, says to himself or anyone in earshot WTF does it matter where you get B+ from?? This thing sucks! He rips it off and goes back to the trusty 3310 that never left him stranded and doesn't need any wires. Sadly, I've witnessed this kind of thing firsthand with my one of my neighbors.

Takes patience but you also need an open mind.