Get a helmet that fits (different brands are different shapes), and is comfortable. There is absolutely no point having a helmet that is so uncomfortable that you undo the straps all the time to ease the pressure.
I found that Giro's are too wide, whereas Spesh fit just right - my head is long and thin.
It's also important to get the straps right. The straps should hold the helmet tight enough that you can't push the helmet around on your head. Too many people have their helmets loose, or pushed back on their head.
Also be careful with the helmet - a hard knock with a lock, say, whilst the thing is on the floor, or in your bag, will compromise the helmet. And make sure you replace the thing after a couple of years.
Get a helmet that fits (different brands are different shapes), and is comfortable. There is absolutely no point having a helmet that is so uncomfortable that you undo the straps all the time to ease the pressure.
I found that Giro's are too wide, whereas Spesh fit just right - my head is long and thin.
It's also important to get the straps right. The straps should hold the helmet tight enough that you can't push the helmet around on your head. Too many people have their helmets loose, or pushed back on their head.
Also be careful with the helmet - a hard knock with a lock, say, whilst the thing is on the floor, or in your bag, will compromise the helmet. And make sure you replace the thing after a couple of years.