Removing the airbox is annoying. They first created the airbox and built the bike around the bloody thing. It does come out but at a certain angle only.
Some report it runs fine without a tune but I would be hesitant to do that to a new engine. Be prepared to tune the bike, especially if you already have an exhaust fitted. The tune part is what has kept me from doing it at this stage. Airbox removal and removing the throttle restrictor (Australian model) will really throw out the tune.
Interesting, about the best info i've read/found so far.
As for the tune from what I understand any aftermarket filter will require a power commander or ECU flash. In two minds on the 'gaping hole and filter' mod as for now will be keeping the bike shape closer to stock than the yard builds and not sure how it would look.
I may just have to take the bike apart to see what it looks like (will post pics if I do). Thereafter it's a debate, is the PCV5 and aftermarket filter worth the cost??!!!
(lol, yes i know it most likely is,but at a cost of 5-6 hundred pounds and the future resale value is never far from the back of my mind. Along with suspension mods and R6 throttle tubes

).