I drove both and the 2006 HCH is not much better than the 2005 in terms of hybrid tech... it is a better car though. Much better steering and not nearly as weak as the '05; I rented a 2005 HCH and it could not accelerate up hills at highway speeds, it was ridiculous. I didn't even try it on mountains like I've driven the '06 over (though it does suffer on them; the engine's only 93 HP).