There wont be any differance in gloss or denim, denim is only gloss with flattening base added...
Durability and scratch resistance will be the same, just more obvious on the gloss.......
Plenty of other colours look really good in low gloss as well not only black.
There seems to be a big return to straight black at the moment and im guessing in 12 months
everyone will be sick of black, just my guess............