my biggest fear with EFI is if something happens to the ECU hours from home. not getting one of those at the local parts store. a sensor no big deal since most use common off the shelf parts..
A well designed ECU, is the most reliable part of the system. Fuel pumps, sensors, and connectors typically fail first. I have never encountered a failed ECU in all my years.
Electronic things in general are very reliable, unless you include iphones in the mix.
