I have a 4 buckle model and found they ride up as well. What i did start doing was wearing swim trunks with belt loops, I wear an old belt and have attached the bottom chest strap from the pfd to the belt via some extra quick clips I got off of an old back pack. Works great, pfd stays down and shorts stay up.
The pic shows a fire rescue pfd but basically my setup is the same. I go through the waist belt rather than between the legs as it is more comfortable.
https://uploads.tapatalk-cdn.com/201...ec94c20e3a.jpg
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