I've got two pairs of ExOfficio shorts, they work well.
For those who have a Marshalls or TJ Max in the area, I got a set of UnderArmor boxers that fit me better and are more comfortable / supportive on the bike, and dry just as quickly.
$9 (IIRC) compared to the $26 the Ex Officios cost locally leaves my wallet a bit heavier, so maybe not as weight saving
For further weight savings, here in SE Asia I've switched to mostly technical wear like EMS Techwick lightweight short and long sleeve Ts. These roll up into very small packages, maybe twice the size of the boxers, and don't take much longer to dry.
For shorts I also use EMS hiking / all purpose shorts. One set in particular is very lightweight, and can be worn without briefs as they have a built in liner. Also dry very quickly, maybe just a bit longer than the briefs.
All this stuff breathes very well, and moves sweat from the skin well.
I just returned from a trip of several days using just my laptop backpack as luggage. I doubt my clothing took up more space than a loaf of bread, and I had a fair bit of clothing: two shorts, 3 boxers, 3 or 4 shirts, and I could have done with much less if on a bike tour.
Only shoes were a pair of Teva Fi 3s, that get used for running, walking, riding the rental bike, swimming (coral and sea urchins necessitate footwear), eating out and the rest.
I caught a ferry to the island, rented a bike for $6/day there, and rode around in shorts, sandals and tshirt for a few days. Helmet plus strap sandals = island ATGATT...
Similar gear can be found in the action wear sections of TJ Max and Marshalls, and I tend to buy stuff at the local Eastern Mountain Sports when they have a sale on.
Of course I have the advantage of riding in an area where temperatures vary from about 70 to 90 or so, and very seldom either side of that even at night, so warm clothing is not a priority.