There are no heavy diesels manufactured with RV only in mind.
Most of them are design for heavy trucking and RV use is just side business.
I can only guess, when you ask diesel mechanic about his opinion -it will be based on commercial trucks, not on those few engines used in RV.
Still remember one of the members here reporting that he rebuild old Detroit (in his dump truck?) for about $12k.
Even newer engines save fuel, their cost would take decade to recoup.
Per my experience with wet sleeves, the major difference for RV owners is checking SCA balance. Additional task to do every few months.