A friend of mine had an Atari 800XL and I thought it was awesome. At the time, all I had was a wimpy Colour Computer 2. I constantly went to his house to play all the great Atari games - so much that eventually he got sick of seeing me. But that was okay because a few years later I got an Amiga
Commodore fans usually consider the Amiga a kind of sequel to the C64, but to me it was more like a next generation Atari 800. I think the Atari 800XL is the ultimate 8-bit computer just as the Amiga is the ultimate 16/32-bit. (and Jay Miner designed both)
My top 5 Atari 800 games:
1. Montezuma's Revenge (16K version)
2. Ballblazer (Ballblaster)
3. Rescue on Fractalus!
4. Blue Max