Actually forgot to go and see 1 today. The shop was way too busy as they had and open day with various BSB stars in there. I'll just have to wait till the NEC to try 1 on. My mind is made up though, so long as it fits right I'm having it.
I have M5 Daytona, Shoei head. You have to bear in mind that if you're buying in UK chances are it's an Italian lid. US made are mostly for US market. And an italian helmet... is exactly that - very nice looking... but lacking in build quality. That's strictly IMO after using it for abt 7 months. I've actually bought a Shark and Bell's now collecting dust on the topshelf. The visor system is not practical (taking it off requires allen key and wrecks the area around fixings). The visor doesn't fit properly / there's a slight gap at the bottom (probably a mechanical fault). It's quite fragile compared to any other lid I've tried. And try and find spare parts for it - you'll probably need to order from Italy. All in all good old Shoei beats them all for me..
I tried an agv k4 evo on Sunday.... Cheap, and fitted well. I have a shoei xr1100 at mo, but will get the agv as a spare. It looks and feels nice.