I have had an adjustable DT for 6 years.
Lost one of the ball bearings couple years ago, don't notice daily rattle anyway.
It is rated for 14k but good luck finding a SS ball rated that high. About 10k will be your max but that is usually sufficient for 2".
I spray wd40 1-2 times a year to keep the lock lubed and avoid difficult turning.
Heavier trailers will usually use 2 5/16 which are not a problem finding higher ratings.
I use a $5 craftsman bag with alternate balls, wrenches and light adapters for 4,5,6 pin
1991 MariStar 240sc, 454, tower, WetSounds, Krypt and Rockford Fosgate