The more expensive the helmet, the lighter and more ventilated it will be and still pass safety regulations. The regulations just specify a minimum; a full face downhill helmet will offer better protection than an ultralight road helmet but who the heck is going to wear one on their road bike.



I had an old Bell helmet and once I tried on a Giro Atmos, I could no longer wear that Bell helmet. The cost of that Atmos has been amortized to almost nothing per ride so it really wasn't expensive.