Sennheiser
Apologies for bringing this back from the bottom of the list, but I have a set of Sennheiser HME100's which i bought brand spankers off eBay for £100. I have used these for a few hours and really like them, they are comfortable and block out the noisiest of cabins.
The only thing I haven't tried is peeling the rubber pad off to change the ST-MO switch. If it works, dont fix it...
I have no idea how clear I sound as I never listen to myself, but I would imagine it is pretty good.
99% of people I see down Shoreham have David Clark headset's. I purchased Senn's because I know they make decent Hi-Fi headphones and earphones, plus I wanted to be different...