As previously noted, I was in a crash and cracked my helmet ... so I had to order another one to use for an upcoming race (The Shamrock Scurry 5K on 3/8/14 in Tallahassee, FL). It is now in - a Limar 757.
I'm very impressed with the fit. The short run tomorrow will give me a good idea how it's going to work out for the long haul.
I can't say enough about how important it is to use a helmet (and other protective gear) while racing in a chair - even if it's not required. This is what the old helmet looked like:
That could have been my skull!
Even if you aren't concerned, I'm sure you have others that DO care about you. Play it safe!