Straight for me. I have only a couple of bent ones, and one to come, but my best smokers by far are straight pipes. My ideal pipe is a straight billiard under 30g of weight; That's what I usually look for, although I get carried away by the beauty of some bents.
I have a pipe rest in every table. I don't like to hold the pipe in the mouth too much; i prefer to leave it in the pipe rest, do whatever and take it back, or keep it in the hand, if I can. Even the bent ones bother me if they hang in the mouth too long.
Despite that, I am more known around these parts by those bent pipes, which I smoke to/from work riding a motorbike...