The closest experience I've had to that was one of the 4th edition experiences at my local game shop before the release, where we had the pregen character cards and ran the mini adventure. Think I got the cleric. However, let's face it - just another rendition of Dungeons and Dragons, so I knew the rules; roll a d20, add a number, beat a static.
So in all honesty, I've never had the chance to experience what you're asking OP, though I think it might be interesting. I started playing 28 years ago by picking up a boxed set from a gaming store because 'it looked interesting' and played with my cousin. I read the rules, ran the game for us, and we expanded from there.
We played 2nd edition up until 3rd came out. On release day, my group chipped in and bought the books. They gave them to me as a gift so I didn't have to shell out all the cash myself and said "We play in two days - we expect you'll have them memorized and we can make new characters and try out the new system right?"
So I've always been that kind of guy; get the books, learn them, play them. I imagine I might quite like to go into something blind for once. Could hate it, could love it, but it'd be an experience.