I've also been looking at plug-in hybrids for a while now (used, though). Aesthetically the Prius 3 appeals more to me than the Prius 4, but the latter has double the charge, of course (8.8 vs 4.4 kWh). Prius is renowned for its robustness, low maintenance, etc. Other than that the Hyundai Ioniq looks interesting. I don't know what else there is on the US market, assuming you're from the US.