I played the entirety of the GMS beta back in like 2004 or 2005 or whenever that was. When official MapleStory launched, I got a bunch of sweet Scania usernames like "Jesus". I have very fond memories of my MapleStory beta days, but I did not play official GMS for very long, because by the time that official GMS had launched, I had already played JMS to 3rd job so there was really nothing new for me to do.
That said, I'm can't see myself playing this, except maybe to download it and play it for a minute just to say that I did. I played some MapleStory pservers a couple years ago when I got the itch (after having played Reboot to the mid 100s in like a couple days) and I have to say that I think the "post-Big Bang" MapleStory experience is much better. I wasn't around for the Big Bang, I quit well before that I think, but I think I'd rather play a modern MapleStory pserver than play an official relaunch of original MapleStory. The old jobs just weren't very fun when you get down to it. Post-BB is much closer to an actual video game, even if it's super fucking bloated with "content".