Most folks stick with engine manufacturers products, especially during the warranty period. Yamaha Ring Free and Mercury Quick Clean are used to help clean up injection system and engine carbon buildup in the motor. I doubt there is little if any difference in the products. As far as oil goes, I would stick with your engine manufacturers brand as that is what was most likely used by the previous owner and the motor is just used to that viscosity and additive blend. Don't neglect your fuel system. So many problems caused by ethanol fuel. Use a good fuel stabilizer at every fill-up. Doesn't have to be the motor manufacturers product, although both Yamaha and Mercury make a good fuel stabilizer. You will get many differing opinions on which fuel stabilizer is best as there are a bunch of them out there.