I have a large assortment of swimwear. My preferences, in rank order, are as follows:
No Swimwear At All Its natural, free and easy; it cant be beat for comfort; and it allows unrestricted access to the main goods for your own and others amusement. Only appropriate for select venues.
The Classic Speedo I prefer nothing too fancy, say in a solid color or maybe with racing stripes on the sides. A Speedo shows off narrow hips and a trim waist, but it also they are not appropriate for all venues because of the highly provocative eye-popping bulge factor. A Speedo hugs your cock and balls, putting your alpha-male assets right out there.
Square-Cut (Lycra) Trunks These are not terribly less demure than a speedo in respect to the celebrity of your big boys, but they can be a good option when a speedo is not the most appropriate choice for some reason.
Boxer-Style Trunks I like these ok as long as they are not way loose or too long in the leg. You can get into some fun prints and patterns without them looking unattractively sissy. This style is a practical choice, when necessary, for taming the visual impact of large genitals. If desired, one can find some that have a snugger fit that still compliment the prominent feature of which we LPSG guys are so proud, but without being over the top.
Board Shorts or Baggies Option of last resort. This style provides more coverage for avoiding sunburn or for using less sunscreen. These can be worn as walking shorts, and they often have pockets, which can be handy. These provide a very safe disguise when in Bubbaland or Redneckville.