The reason I don’t recommend buying a used Optimax is based on my experience with a new 115 HP. I went through about 18 months where just about every component on the motor failed including the block and lower unit. All these were repaired under warranty but it spent more time in the shop than on the water. I will say that once it was completely rebuilt, it ran great but the memories lingered.
I have fished with the same club for 45 years and have seen all the brands go through engineering disasters. Most of that time I was driving EFI Mercurys and had no complaints other than excessive gas usage. The majority of the guys that tried Opti’s had problems but a few were ok with them.
During the 8+ years that I owned the Opti, I also had a Yamaha on my Pontoon boat so total cost of ownership was an an easy comparison. The Opti was really good on fuel consumption averaging about 5.0 to 5.3 MPG but oil consumption was another matter.
I normally bought 1 gallon of oil per month at $32 per gallon. Even at a conservative 10 gallons per year that is $320 as opposed to one oil change per year in the Yamaha at $45.
I posted quite a lot about my perceived excessive oil usage and some owners posted that they were burning 60 to 70 gallons of fuel per gallon of oil. There was no empirical evidence available so I created my own. The attached spreadsheet screen shot shows individual test instances and a summary of oil and fuel usage on my motor.
So while there are a lot of happy Opti owners out there I’m not one of them.