As a player, you just have to show up. The problem is managing player expectations. "No you can't just charge in and kill everything, the guards note your feeble attempt to kick in the inner door as you bounce off the bullet-proof glass. They've maglocked the front entrance and are calling the police. Does anyone have an electronics kit to try and disengage the maglock? A prybar? Anyone? Anyone?" is a hard thing to hear when you're used to killing orcs and taking their stuff...I was a D&D-snob even having played other systems. Thankfully, I've recovered and in doing so have seen the flaws in earlier editions of D&D for the gigantic warts they are. Yes, I had fun, but I will never run or play AD&D2E again.
I agree that trying new systems is much easier as a player than as a GM trying to get others to try a system out.