Sonic 1-3 vs Donkey Kong Country 1-3
First off you have to take Sonic 3 as is so no Sonic 3 + Sonic and Knuckles. My opinion is Sonic > DKC. DKC 2 vs Sonic 2 is a tie. and DKC 3 > Sonic 3. So I got it as 1-1-1. I fully expect to see some clean 3-0 sweeps for Sonic here. :)
My reasoning is that DKC is overrated and not that good so Sonic beats it easily. Now Sonic 2 and DKC 2 are both my favorite games in each trilogy so I went with the tie. It was too hard to pick 1 over the other. DKC 3 over Sonic 3 because Sonic 3 as is, is unfinished and DKC 3 is polished and complete.