I gotta go with the Xbox None (never had an Xbox)

OG Xbox.
- Halo.
- Halo 2.
- Fable: The Lost Chapters.
- KOTOR.
- Elder Scrolls: Morrowind.
- Jade Empire.
- Blinx.
- Jet Set.

The 360 era was awesome, thanks to the games and the achievements system. My top 50 list is full of games from that era.

Was lucky I never got RRoD myself, nor any breakdowns actually, despite putting in so many hours on it. So the worst thing about the console for me was probably how frigging noisy it was; I'm glad they eventually gave us a partial solution for that.

360.

My first Xbox and it was like the best thing, ever. I only got one because the other consoles were too hard to find (My track record with PlayStation consoles was sketchy, anyway. They kept breaking.)

My Xbox 360 broke, too.

Didn't matter. Everything the 360 did felt like it was new, refreshing, and on another level. The games were great, too.

Xbox 360. Not only the best Xbox but one of the best consoles of all time.

360 for me. Sadly many of the XBLA games didnt get the jump to XBO as others did. Mainly those from Sega. Afterburner Climax, Outrun Online Arcade, Sega Rally Online Arcade... so many great games died on that hill because of licensing and/or MS just didnt want to make them work on the XBO.

Xbox 360
Mass Effect 1 & 2
Halo 3
Black Ops 1 & 2
Halo Wars
Dante's Inferno

360 easily but the Series X/S could surpass it later in the generation.

Original Xbox. While 360 is a better system and offered me more overall.
I have too much nostalgia tied up with OG Xbox with Shenmue II, Jet Set Radio Future esp plus a number more.
I own more games on 360 than OG but again nostalgia trumps overall. I got an OG Xbox to play Shenmue II and I pulled a 24-hour marathon of playing it. Then I played JSRF and while I did play JSR before on DC. JSRF was so much better. Has one of my fave OSTs in a game. It felt fresh, and futuristic but also just pure joy to play. Still, one of my fave SEGA games and I want an HD remaster for all systems.

My favorite was the original Xbox because it was so drastically different than the other consoles at the time, and allowed for an online experience that was only dreamed of in the console world before. But I think it's obvious that 360 was their best console, all things being equal.