This is a stupid idea. If I were 50, I'd look at 30-year-olds as immature. 30-year-olds might look at 25-year-olds as immature. As you grow, the people much younger than you begin to seem more and more childish, even if they behave exactly the same as you did when you were their age. Setting an arbitrary cutoff date (at 18 especially, when immaturity is rampant), is just unfair.
wouldn't make any difference, there are tons of retarded 20+ yr olds that still act like kids. I've seen 30 year olds who are raging idiots trying to save face and do all the stereotypical MOBA player finger pointing stuff.
If you believe in Goku, and are 100% proud of it, put this in your signature.