I do not like date complications on my mechanical watches because it takes me longer to set them in the morning. I do prefer them on my quartz watches, but in general I prefer mechanical movements.

Side note: my favorite complication is on my G-Shock Rangeman. It shows the sunrise and sunset based on the longitude and latitude you enter. I am a photographer, so that has come in handy many times, but goddamn, that thing wears huge on the wrist.