It depends on the person--some people are more mature for their age and very responsible, others aren't. A ten to fifteen year age difference might have been more acceptable during your grandparent's time. You must also take into account your compatibility--the more pronounced the age gap, the less you may have in common as a couple due to growing up in different decades. Physically, if you are 10- 15 years older are you going to be able to keep up with a younger woman? The average 60 year old male has far less energy than a 45-50 year old female. Again, all points for consideration but it all depends on the couple involved. Best of luck!
In past generations, women were married at 14 or 15 and having very large families. I have heard stories in my family of 23 children and multiple sets of twins. In my own immediate family I am one of 7. An older established gentleman can also offer more financial stability to a younger woman. In those days, however, children died very young. So they had a lot of children to help work the family farm and take care of the parents when they are older.
Where the issues occur is when one or the other of them are really not happy with one another from the beginning, but they have a marriage of convenience or compromise or quid pro quo, i.e., she has something that he wants (beauty, sex appeal) and he has something that she wants (money, property, security, etc.). Of course this is a worldly arrangement; the foundation is wrong. I see older rich men marrying much younger women for their beauty, and this is not at all a good thing, because after 10 or 15 years at the first wrinkle, he is looking for the next young beauty to take her place on his arm. Here in Louisiana, Edwin Edwards (Democrat politician) and Al Copeland (Popeyes Chicken) come to mind. They were each married multiple times to 30 something women.
Marriages that are founded in the right way last no matter the age difference. Marriages that are not founded the right way, fail. Seek your discernment with God in the process and it will succeed.