I think the age should be lowered, but not by much. The world's youth has basically been desensitized to violence and other themes anyways. So lower to 14 or so.
In my opinion it's really how mature you are and how you can take it in. For example, if your some 12 year old who plays games like GTA and tries to imitate that then ,of course, you shouldn't play those. But if you 12 and can handle and take that in with out going crazy, then sure. Play all you freaking want.
Yeah, You should be atleast 17 or up to buy a M rated game, Becuase if a child is provided a role model such as niko ( I don't know the proper way to spell) Then they will think hurting people and swearing is cool. I know this sounds cheesy but seriously, i wanted to be like the power rangers so i jumped around and tried to do karate but obviously failed. At their mind rate they will imitate just about anything!
id say at least 16 cuz im tired of most kids under tht being so damn annoying if uve noticed ive met some tht are ok but they dont make up for the rest and this is for multiplayer games but regularly i dont care wat age ive been playing m rated since i first got a good system
in other words as long as u can handle the game without wetting yourself u shuld be able to play it and if u do its not the games fault cuz it tells u the first good system i ever had was the Ps1 in 1998 (i was 6 then) my uncle had some games but i guess those graphics arnt nearly as good as they are now so its different u get a Ps3 and play resident evil its intence but u play it on Ps1 and its like wow thts it