Do yourself a favour and don't buy a cheap plastic helmet. Thermoplastics (polycarbonate in this case) are reserved for companies' low end models. As for that, it's a decent low end model but unless you pick one up for 50 bucks, I wouldn't bother.
You can generally find a nice composite shell (fibreglass, carbon, kevlar, etc). helmet for $100-200 if you search around (especially online).