I had an IRH last year and loved it! Had a minor concussion at a show, and it saved my life!!! Best $40 I've ever spent. After my concussion, I splurged and bought a Samshield, but honestly I felt like my IRH fit my head better as it was adjustable!
I agree Charles Owen the helmet is the biggest safely item in riding and a good quality is a must! I would rather spend money on a nice helmet that with protect my head well rather than a cheap one that won't offer much protection