I took this from the HADA board good advice..
As long as the helmet has a snell M2000 or better sticker and it's new it's safe enough. A new cheap helmet is much safer then a used expensive helmet with an unknown history.
If you payed $350 for a helmet I hope you got a quality Snell SA motorsports helmet (rated for multiple impacts and provides fire protection). Instead of waisting your money on an expensive Snell M series motorcycle helmet (unless you ride a motorcycle of course )
Open faced Snell M2005 helmets can be purchased for less then $100, but they may not be the most comfortable. You do get what you pay for afterall.
In fact I paid well under $200 including taxes for a Zamp brand full face (with a shield) Snell SA2005 motorsports helmet from Carl Wener at TRAC racing.
Zamp Racing - Auto - FSA-1
I find it almost as comfortable as my $350 Bell Snell SA2000 open faced helmet.