Quantizing multitrack drums with time stretch

Hi,I have a small section of a drum performance thats just a hair too fast and ruining the feel of a track.I usually just slice and move to solve these issues ,but in this case its not working too well.I have never bothered with stretching audio before,as I can hear audible artifacts.But in this case id like to move a couple of hits just a fraction.Seems the only way to do it ,is in the quantize panel with audio warp.But even moving it a tiny amount, the artifacts make it unusable.Now I have also just set the files to musical mode and changed the tempo down 20 bpm, as an experiment and the artifacts are minimal compared to what im getting using the quantize panel.Am I missing something?There doesnt seem to be an option to just grab a hit and move it in the project window either.This is with group editing set for the multiple tracks.Also if I move multiple tarcks will it mess with the phase coherence?Cheers