Check out this approach to painting doors. Its faster and looks just as good as brushing, almost ;) I still prefer a brushed door but the rolled method is great either way.

The paint used in the video is called Sherwin Williams Qualikote Semi Gloss. It is the best semi gloss for interior trim, doors, etc... hands down. Most other products dry too fast- leaving almost any painter with a streaky mess. Yuck!

The roller used is a Sherwin Williams 4inch Contractor Series Blue Knit. I Use them all the time!