I have been using a Petzl Elios for a couple of years now, and it has its' good and bad points; as far as comparing it to other style helmets, I have no point of reference, since prior to that I used a hardhat. I have not had a serious rockfall on it, so no comment there. It does seem somewhat warmer than my old hats, probably because I wear it both in and out of cave (ridgewalking). One drawback is, for those who like to store emergency supplies in their helmet, you won't be able to do so. It seems to balance just fine.
Like I said, I've had mine maybe 2 or 3 years, and it has held up fine so far.
Trogman