Back in the UK I have a Shoei Raid II road lid and out here in Oz I currently have a Thor Force Carbon fibre MX lid... have to say there are some aspects I love about the MX lid and other bits I hate, when on the road.

I love the light weight and open ventilation during hot days with the Thor. I also don't think I could live without the peak after getting so used to using it to avoid things hitting me in the face when on dodgy roads or just keeping sun out of my eyes.

However as said above its noisy, if its cold outside its not pleasant (just brought a thin balaclava for early morning riding to try and solve this) and if traveling at speed (over 50-60kph) during rain you have to ride one handed to block the gap between nose and goggles to stop your face stinging.

rain can hurt alot! I ride everywhere with my mx helmet and once a bug hit me in the nose, at first I thought it was a wasp because it hurt so much.

Something in between.
 

I've been reading good reports about the Givi X.01

http://www.givi.co.uk/bo/allegati/Im..._2008-N900.jpg

which looks like an interesting idea. You've got a full face for winter riding or whatever, and then you just swap various bits over and you've got something with loads of ventilation. I've even seen pictures of people using it with no chin guard so in fact you've got three helmets in one. Not as versatile as a flip front maybe, but at 1400grams or less it's not that heavy either. Aooarently it's been tested with both chin guards in place.

Thing is I've not seen one anywhere, has anyone tried one?