This is highly individual. There are a lot of women who feel thongs are very uncomfortable and they won't wear them for that reason. Other women are neutral about them and don't mind them. And yet others find them actually very comfortable.
I could be considered weird in that regard. To me, thongs (and g-strings) are actually the only kind of panties I ever wear, because anything else feels rather annoying to me. I'm so used to thongs, I can't stand the feeling of having anything else covering me down there.
But either way, this a perfect example of a good old "to each their own". :)
Don't like them and they give me urine infections after wearing them for an hour. Having a piece of string running over my bumhole and then straight over my vag is just a silly idea... why are pantie lines a turn off? All it does is make the guy imagine your pants... how is that a turn off?
I find thongs really comfortable. I wear thongs all the time and while the strap can be noticed sometimes, other times it rubs me in a good way back there. I love the way the feel up my ass.
I think it depends on the fabric, they make man thongs, and at the end of the day every piece of clothing fits a little different based on size and material. It is not so bad though because boxers are kind of bunchy in tight jeans and briefs act like a heat lamp of the crotch a little too much.