Well, that's a tricky question (somehow reminds of the troll polls era, though). I rotate scissor switches and MX Red (when my fingers feel sore, especially due to bottoming out on worn RDs), but I wouldn't say any of these is truly my favorite switch. I believe Topre or ergo clears could be high on the list... However, it doesn't matter at the end of the day. I could live with some higher-quality rubber domes and wouldn't complain. It's just a matter of adjustment, and from the ergonomic point of view, it's layout what makes the difference.
My favorite switch would be either a low-force silent buckling spring, or lubed low-force MX Clear (hard to bottom out, unlike ergo clears). Unfortunately, neither exists.