Then why do you want plug-in hybrids? They not only have all the technological gizmos that might break, but they also have all those other mechanical things that can also break, not to mention, add a ton of weight; Batteries AND drive trains (Engines, transmissions, differentials, drive shafts etc.)
They are the worst of both worlds.
what's the difference between a gas-electric hybrid and a plug-in hybrid wrt gizmos?
My experience with owning a couple of gas-electric hybrid is that they get significantly better gas mileage than the equivalent ICE-only vehicle. By "equivalent" I mean same make/model such as the Escape and the Escape hybrid.
It is my understanding that the plug-in hybrid will get better gas mileage than the gas-electric.... how much better would be a function of how often the ICE needs to run. And, of course, the electricity from the wall needs to be accounted for... it ain't free.