My wife's male friends sometimes will slide into my while we are in a pile or while she takes a break but i cannot imagine doing it for like an hour. Most times we are finished in less than 10 min.
It had been college since I've seen men fuck other men live and you are correct, most came quickly but there were always some that lasted a decent amount of time.
I have found couples who swing regularly and got an invite to come check them out. One of the wives heard me and a girlfriend talking about wanting to see our lily white husbands taking bbc up their asses while having bbc's stuffed in their mouth, bareback, cum filling. The woman said they have three gorgeous bbcs in the group and they fuck their men plum silly. Since I was last on here we've been talking, hanging out, getting to know each other. She flat out told me she wanted to take a dive down on me one day, preferably sooner than later.
This past weekend two of my friends and I were invited to see their men in action. Honestly I thought it might be a set up to get into our pants. The lady is a fairly aggressive. Oh MY GAAAAHHHHHH it was for real. We walked in to WHAM three white men bent over doggy getting the fucked so well I wanted to strip, bend over and over myself up. My friends told me later they felt the same way. It was some serious shock and awe. My eyes were glued. I think I orgasmed standing there gaulking. They had to have been at it for a while, there was cum all over all of them. We watched for over an hour more as two of the black men came inside never getting soft continuing to fuck that white ass. The third didn't appear to orgasm until around an hour plus after we got there. The other two orgasmed a total of three times before stopping for a break. A break? You've got to be kidding me. Nope they were cleaning up, breaking, then fucking the white men more. We watched the black men fuck the white husbands of and on for hours.
In between we saw the wives get it on as well as during. The wife who invited us as all over the place eating all the wives. I admit she was a hottie. None of the women got fucked by the men. It was all women and all men. I never in a million years thought (I did hope) I'd get to see this live again. I was so darned wet I was soaking through my cloths. Each time the bbcs pulled out of the men the cum flow was so amazing, the view was naughty hot, it was everything I could do to keep from getting naked and masturbating like mad.
I knew I'd get myself in trouble if I stripped so I watched while squirming - A LOT! I didn't want to leave but finally my girlfriends dragged me out. We thanked the hostess and told the men it was the hottest fucking we'd all seen in a while, thanking you profusely. We were invited back with our husbands.
I have yet to tell mine about it. Not that I am scared to, we have been nutso busy. I plan on talking with him tomorrow morning when we have a few hours.
So there are those who can do it apparently quite well for long periods of time. I doubt it is the norm though, as you have all pointed out, but these gorgeous bbcs certainly had stamina.