I am one who is VERY allergic to scents and the foam does not bother me at all. The smell is very light, it is the same smell that you get from mousse, it is not a bad smell I think it's ok actually.
Eventhough the smell is barely noticible, in fact I find the smell to be pleasant, I would still buy the "unscented" version if they ever made it. However, no such thing will happen i believe, every foam, whether it's stlying foam or whatever has some sort of distinct smell. There's no such thing as a product that has no smell at all.