I am in the camp with WizarDru and Wisdom Penalty. Game prep time is the big key here. Our group is mostly 40+, with some younger (my teenage son, for example). I'm fairly certain the players would be fine with 3E, AE, 4E--or for that matter, Hero, Burning Wheel, or any number of games--assuming that I had enough fun prepping and running it to not burn out. If your GM starts to fade, things can get bad, quickly.