I am 51 and have been in a committed relationship for the past 5 years with a man 8 1/2 years younger than I.
Prior to meeting him, and after my divorce, I dabbled in the dating scene and did have a little fling with a guy 26.
While it was all in fun, I don't think I would want to date someone as old as my kids, so 10 years my junior would probably be enough for me.
That being said, I think that everyone's personalities and preferences are completely different. I think people with age differences can certainly have a great time together and even be a long term match. it just depends on each individual.
If you like the guy...and he likes you....go for it!