I've got some over-the-head ones I like, that only become uncomfortable after somewhere between one and two hours, but most others I've tried, including the softphone headsets we've all been issued with at work, become uncomfortable after about ten minutes due to pressure on the ears. But I find the in-ear silicone bobble type ones to be remarkably good for long-term use too, especially as compared to the old solid-plastic type. (And my comfy over-the-head ones are, umm, now I think about it, fifteen years old now so they're not really available any more.)