I knew one person that had a Colecovision when I was a kid and I remember just being "wowed" by the graphical differences (for the better) on it as compared to the 2600, which it seemed like everyone had. I do remember that DK absolutely sucked on 2600 but it wasn't nearly as bad as Pac-Man. I can still hear those awful sound effects even though it has been nearly 40 years since I saw or heard it.
RE: Fan Fixes Atari 2600 Version of Donkey Kong in Homebrew Remake