i have a cheap flightcom headset ($395A in 1997), gel seals, electret mic (whatever that means) and big cussion at the top. its great! strait cord wich i have had cut and a nato plug and socket inserted for use in both planks and heli's. nato plugs cost about $45 each ($90 for both). a bungy corded one would have been good but they get cought on everything too.
$8 sunglass seals work wonders!
p.s. i used a new david clark to day to see what the difference was (a cheaper one, $500), the sides were more adjustable (probably cause mine had more padding on the top) and it made my speech sound robotic and almost hard to understand, aswell the mic was big and ugly and had no wind sock, it was a silly pastal blue colour aswell.