I’ve heard that some mechanics are near refusing to work on them. What’s with that?
Not sure where you heard that but I am sure it was most likely from a guy that is in love with his Merc.
I bought an early model 2011 250 SHO and it too has been flawless. I ran it for six years without a hitch. I know some of the 2011 250's had faulty oil pumps that led to catastrophic failure but they stood behind every one of them.
Last year I got a letter from Yam saying that my serial number fell into a group of motors that could potentially experience oil pump failure. They told me I had one year from the date of the letter to take it to any authorized Yam dealer and have an all new powerhead installed.
I waited until this May then took it to Fun N Sun and they did just that. I have 4 hours on the new powerhead and it runs like a scalded ape on my Legend Alpha 211.