IMO, pointing it up looks sexier than pointing it down. Fabric plays an important role with penis position in a brief racing suit. Nylon suits will not hold it up. It will either slip to the side or down. Lycra will hold it either straight up or up and to the side.
For me, having my tool hang in a pair of briefs, whether a swimsuit or underwear, is uncomfortable. I don't like anything tight around the head. I have a few Speedos, and will wear them once in a while, but I favor freeballing in a pair of mesh gym shorts for comfort.