I've been using one of the "Sport Integral" helmets for the last 3 years (until last month, when I finally decided to go for a flip-front), and can give you my comments as follows:
Plus points:
1. Very quiet, undoubtedly the quietest helmet I've ever used.
2. Good visibility.
3. Relatively light weight.
Minus points:
1. Worst helmet I've ever used in the rain. Rain leaks through the top of the visor seal and runs down the inside of the visor (Had a total of 3 helmets - they all do that!)
2. The anti-fog coating on the inside of the visor is very sensitive and can come off through normal cleaning.
3. Replacement visors are expensive.
If you're looking for something comfortable and quiet, and don't ride when it's wet, then it's an excellent helmet. I've heard that BMW are just about to replace the "Sport Integral", which is why all dealers have them on offer at the moment.