I get really bad headaches from headsets, but for me it's more because I have a really big head, and wear glasses that get in the way, and the headsets never adjust to be quite big enough for me. 2-muff headsets are more comfortable for me, the one-muff kind just kill me!
While I hate it that my current gig is completely ClearCom-less and we run off walkies from Radio Shack, the best thing about it is that they came with the option of earbud-style headphones with mics that clip to your shirt. Some of the other SMs/ASMs here have said that they're awful, but I -love- them! SO much easier to deal with!