[loudmax]

Yes, my Prius Prime handles highway speeds perfectly fine on battery. In fact, the acceleration is great in pure EV mode.

It just doesn't have much range: only about 25 miles on my 2018 model. Newer models advertise up to 44 miles on EV.

[jeffbee]

Sure, that's the obvious downside of them. But in the role where they spend ~10h slowly charging overnight from a standard plug, about 25-45 miles is all you'd expect to enjoy in a steady state.

I had a PHEV Honda and I put 20 gallons of fuel in it over 6 years. The system works in the niche for which it was designed.