to me intakes like SRI's are relatively the same in design and power figures from the bigger companies like CS and CPe all have the same kind of figures and results once fitted. Only difference being the accesories they offer like the boxes. Only reason im interested in a box is just so that if an officer ever opens the bonnet and sees an exposed filter, they generally dont like that. Having a box or some form of cover just makes life easier at those times. But i'll be running with an exposed filter until i can make something or find something to suit.