For me it's RTwP hands down, it's the reason I liked DOS but didn't love it.
RTwP I find so much more fluid, you can choose to micro manage or not & respond on the fly. It allows for both single enemy fights or huge fights with dozens of oozes or waves of guards. Turn based I find jarring, slow and limiting (most notably you can't really have more than 10 or so combatants). And it limits the number of encounters because the combat phase is so long.
The downside of RTwP for me is it's less true to tabletop; but I do think that can be adjusted if you somehow included, for example, some sort of initiative roles at the start of combat. Nevertheless, I do feel it works better in digital format than turn based.
