Thank you all for the great responses. I think from all that has been written the Bose X sounds great, pleasing more pilots than it displeases. I will try one out when I am next back in the uk and then make a firm decision. I also read about the Lightspeed Zulu which was in the mail order catalogue of a reputable Pilot shop, which sounds pretty good too. Overall though from the responses I have read the Bose sounds pretty hard to beat.