I was thinking about this last night, trying to work out which editions I have played the most. I'd be interested in seeing what others have played.
While I think that 5E will eventually take the top spot, it hasn't been out for as long as I played some other editions for yet. But it has all the time in the world to catch up. That said, here's my estimated ranking, although I'm not 100% sure.
- 2nd Edition. Definitely the one I played most, and the one I had most material from. I played this for 10 years at least, pretty much solidly, and really had a ton of stuff.
- 1st Edition. Another long one, but I was a little young to start it when it first came out. I started playing this at school in the early 80s, until 2E came out.
- 3rd Edition. Including 3.5, I played this for about 5 years, I think. I'm not completely sure! But again, mainly solidly, although there may have been a couple of short campaigns from other games in there. I ran the entire Age of Worms adventure path from Dungeon Magazine, plus two home-brew campaigns.
- 5th Edition. It's been out for 3 years, and I ran Curse of Strahd, and am currently running a 5E Middle Earth campaign, plus I ran the Starter Set when it came out. I suspect this one will eventually catch up with 2nd Edition, but sheer longevity will mean it'll take time. It probably ties for Pathfinder right now.
- Pathfinder. I've included this, as it took over the tail end of 3E before we tried 4E, and then we went back to it between 4E and 5E. I'd say I've played about 3 years of Pathfinder in total, at a guess.
- 4th Edition. I played this for maybe a year.
- OD&D & Variants. Too young for these, I have played them since, but not for more than a few months.
A lot of this is based on hazy memory, and I could be wrong. And, of course, there are other games mixed in there.