I don't wear underwear all the time, but when I buy boxers I have ordered custom made online at CityBoxers.com...the ones made from dress shirt material are great and they will make them to your exact size and the length leg you want and fly opening too. I go for the longer jammer length legs. also buy big baggier Abercrombie & Fitch boxers..again..nice long legs and big fly openings are a must.

for undershirts--or I think you call them vests in Brit speak...I get Kohls private label here. only wear athletic shirt type and Kohls brand have really really deep armhole and are long enough to stay tucked in. I like the deep arm holes that reach almost halfway down your sides..real comfortable

for jocks I usually get Duke brand at Internationaljock...but will but others I see.