Here are some of my thoughts.
In India its a fact that women need men to protect them. (please dont come with arguments of exceptions, just think is it practically possible for a young lady to travel alone in an unknown place at night? How many are willing ? They need some one to take care of them in most instances except family business!)
Since its men who take the role of a protector, caretaker, It wud be good if he is a bit elder than woman.
Regarding maturity and all-- it depends. If u r matured enough, then no harm!
Then there is another reason which tells why men should marry younger women.
Women looks older than a man of same age. So to avoid issues arising from 'inferiority complex' of women regd. age, its better for guys to find girls younger to them by 3 years atleast..
Anyway, sucess of marriage is a function of proper understand and caring of each other, so if tht understanding and caring is there , age is not a barrier. but in a practical scenario,, i wud go for marrying a girl younger than me!