hey Paul.
I'm in exactly your position, and decided that spending money on a decent headset would be worthwhile. So I got a Clarity Aloft...
http://www.clarityaloft.com
It's a bit unconventional, but I cannot recommend it highly enough. Amazingly comfortable, very effective isolation from cockpit noise, superb sound quality. Check out some of the comments on the interweb - seems like everyone else is as pleased with it as I am.
mtw