Kaspersky: In terms of overall protection Kaspersky is the best. Excellent signatures, cloud protection against new threats, solid web protection, industry's best behavior blocker and also have TAM which if you enable will only allow trusted files to run. Advanced users can also modify each applications permission, configure protected folders etc. It's probably the most complete package. It's light and no noticeable system impact in my experience either.
ESET: It's excellent as well. Brilliant signatures and one of the best at detecting unknown variants of existing malwares. It's web protection is probably a bit underrated, as in my own experience it's better than the other big guns. Has a highly customizable HIPS and no system impact at all. You're using it at the moment so you surely know all about it. Only downside is not having a proper behavior blocker unlike the other two in your list but since you're not prone to infection, this should not be a big issue.
Emsisoft: Emsisoft is known for its excellent behavior blocker. Even though the Bitdefender's signature has become a bit weak against newer threats, this shouldn't be a concern with you're safe browsing habits and the behavior blocker would likely protect you if something gets through. It's the least customizable AV out of the three but it's fast, light and a great program.
Three great products and it's better if you try the trial version of Kaspersky and Emsisoft before making any decision.