Like most men, this is one subject that I have quite a bit of personal experience with - lol.

I would say the longest time could be 3 to 4 hours.  Obviously not whackin it the entire time.  This would be looking for new video clips for the archive.

The shortest - under 5 minutes by going to my favorite clip.

and see clients..it still isn't enough.

The most 4 or 5 hours and that was a lot of cum and orgasms.

Normally on average now, I masterbate at night for one hour. I love to stop myself before I come and tease myself that way...its so much fun and I get even more excited by doing that.

Shane