The success is heavily dependent on your ability to either A) Understand how EFI works B) Your desire to know about how EFI works. The systems are sold as "plug it in, fire it up and go". While they're quite good, they require tuning if you want it to drive like a new-ish car.

Understanding of IAC operation, how coolant temp effects fueling, rotor/timing phasing, acceleration enrichment, RFI/noise suppression, cold start enrichment, warm-up enrichment, etc. are all going to be necessary skills to execute the swap well. YouTube is loaded with helpful videos on this stuff, but one has to want to learn how to do it. A large portion of the TBI kit buyers simply don't want to do that.

My Father in Law is who I installed the FiTech kit for, he has pretty good carb knowledge but was initially clueless on EFI. Without someone knowing EFI around [me], I can see the process for him being very frustrating, which is where many people who write reviews online find themselves. That said, his truck has never ran better!