Since it is so hard to change the oil in most OPE - I mean you need to remove a drain plug and let oil drain into a container then put the drain plug back in, and then to make it even harder - on some engines you need to use a funnel to refill it!!!!
But the worst part -- I might get my hands dirty - I may end up with that black stuff under a fingernail -THE HORROR!!!!
OMFG I change the oil in my OPE and it cost me $5 more a year since I didn't go 300 hours between changes !!!!!!!!!!!!!!!!!!!!!
Even if you thing ?W50 is the cat's meow -why not change it anyway?