POC Ventral or Octal, if you don't mind the mushroom head look. Several friends wear 'em. Nobody dislikes them. Some even wear the crazy neon colors.
POC Omne Air Spin if the budget is tight and you prefer a more conventional looking helmet. I've had one since last summer. It's by far the best ventilated helmet I've worn. Looks pretty good as helmets go, less mushroom-headish. Not quite up to the fit and finish standards of the Ventral and Octal but pretty good for the money. POC pinched pennies with the Omne on the harness, dial and harness height adjustment, but they all work fine. Just not quite as nice as the pricier POCs. A few months ago Competition Cyclist had several of these for around $75 but prices may have gone back up to the $150 MSRP.
Bell and newer Giro helmets tend to be excellent values, much better fit and finish that some others in the same price range. I'm surprised by the attention to detail in my $75 Bell Formula MIPS, including the sweat channel (sweat drips in front of my face rather than down my forehead into my eyes), protective polycarbonate shell covering the soft EPS foam on the exposed underside rim, adjustable rear dial height, etc.