I am 54, was seeing 50 year olds when I was 30. Now I enjoy women from 29 to 55. It depends very much on the personality of the lady.
My best oral sex was with a 45-50 year old lady who knew exactly what to do to bring me to climax.
I have, over the years, seen many women from 18 up, I enjoy the occasional 20 year old, but keep going back to more mature women.
Naturally I am speaking of prostitutes, not many chances for a 54 year old to 'dip the wick' with someone 30 years my junior, without dollars changing hands.