Hiya JD Miller and thanks for your thread. I've seen some custom kydex holsters built to have the light on the rail, it looks like it could slow a concealed draw. I'd only had a laser on the rail and it was not compatible to holster draws, so not much help there. But having enough cz pistols ,with and without rails,can say my opinion, my experience has been that having the rail can either decrease muzzle flip,or the perceived muzzle flip,which can effect getting back on target. If your budget allows both,its best to have the choice after you have broken both in. Be well.