It had the best gameplay, since there's the fewest amounts of QTEs and scripted crap. Leon's had too much of both, as did Jake's. Ada's is my least favorite; it just felt like we'd "been there and done that."
Chris's also had the most important story, due to Haos.
Chris. It was the most consistent in terms of theme and gameplay. Not only did itmake no qualms about what it was being, but there were the least amount of QTEs and the game makes the best use of the mechanics. Plus it had the only worthwhile story/characters.
Leon started off good (minus the stupid forced walking section), but it just abandoned what it was trying to do in Ch3. I'm not sure how anyone can condone Leon's campaign after Ch2. Plus, zombies are push overs.
Jake is just flat out terrible and Ada is hit or miss.