I got a Genesis for Christmas in '89, and then bought myself a Super Nintendo in '93--which I still have. In hindsight, there's a lot to appreciate about the Genesis/Megadrive and its library of games. When I got mine, though, it was hard for me to leave all of my favorite NES franchises behind, so I sort of knew I'd be coming back to Nintendo at some point.
These days, while I often think of myself as a fairly hardcore retro gamer, that hardcore-ness is expressed mainly in unusual ways, e.g. through hardware hacking of the old systems and contributing to emulator and chiptune software projects. It's like...being strung out on crack as a kid, and then growing up and finding amusement studying the molecular structure of crack.