35 years, started with the box sets, simultaneously dabbling with Avalon Hill and SPI wargames. My D&D experience was partly self-taught and games stories from my classmates (Catholic school) that were in a game in the next county. In the late 70s most of the early RPGers were wargamers that were dabbling with TSR Chainmail and so on. So their games tended to be very gritty and heavy into realism.
When eventually got into a full campaign as a player, it was a very detailed campaign, with many facets of realism applied to monster ecology and the game world.... so you knew where the orcs lived, where the goblin warrens, a dragon live here etc. Adventuring was risky as it would be for a 11th -14th century mercenary, though we rarely encountered diseases that tended to wipe out medieval armies, death came swiftly to monsters and traps, so we tended to roll up many characters during the course of a campaign. Still it was a lot of fun and very immersive. Magic was on the low-end and tended to be more exotic and mysterious, rarely over the top.
My time in the university and active duty USMC tended to be the same, if not more gritty in the gory details of medieval warfare. Dabbled a bit into original Champions, Gamma World, Twilight 2000, DragonQuest, Runequest, and Traveller, but they didn't' compare to a good D&D campaign. I did enjoy a good Top Secret campaign, as the DM ran a long-term cold-war focused campaign. I eventually settled down to my home brew long-term D&D campaign with currently 4 chapters of campaigns that I have run for various groups over the last 15+ years (primarily 3.0-3.5).
Over the last few years have run several short campaigns (6th - 8th level top) Pathfinder and couple of Savage World modern day horror campaigns, and most recently a Goodman Games DCC RPG campaign - which IMO is one of the best retro flavor games out there, much better than Labyrinth Lord, C&C, or Basic FRPG. Probably have forgotten a dozen other games I have played in or run.