As long as the hat has the right safety certificates- like in britain there is BS EN1384 as an example- and fits you properly, its fine!
The most important thing to do is make sure it fits properly. It is a good idea to go into a shop for the first helmet you buy because the people in there will make sure you have a correctly fitting hat that is suitable for your needs.
Tha newly bought hat should feel tight at first because the lining will compress slightly with use. I just got a hat that was a size smaller than my head measurement said it should be and it fits perfectly!