MegaDrive. Don’t remember how I got it, I just always had it. I don’t play it that often if at all anymore as I prefer the ease of emulating on my HTPC with retroachievements. Even got a nice saturn style fight pad that works great for MD games.
Also the model I have is the region free Asian one even though I live in the UK. I’ve always had a JP copy of sonic 1 too. No idea how they ended up in my hands.
I sold my PS2 and every game I owned for it for like 3-4 360 games. About 5 or so years later I massively regretted that. Ended up trying to go for a full PS2 PAL collection, likely to compensate. Stopped collecting at around the 600+ mark.