Uhh 25 is fine.
I mean you did so as a teen... remember those teenage clubbing scenes? Those were lame? Remember when you turned 18 and you went to an 18+ club? Gosh those were lame too.
The first time I set foot in a 21+ club I was drooling. It's way better than anything you've seen before, and if you know people from the clubbing scene like promoters or even people who just go frequently, you'll be going to the right places. I'm not a clubbing expert myself, but I at least know which promoter groups to hit up and I have friends that go frequently. You just need to be going to the right events for it to be fun.
I also have friends that go to ghetto shady clubs because they just find out its a new event, or that people "generally go there," but sometimes they hit up the same clubs I hit up but just on the wrong nights. Yea, in that case without a promoter group, you get ghettoass people showing up adn what not.
25 is fine. I have friends who are 24 - 27 hitting up the clubs frequently. Notice how many clubs say 23+ preferred?