I would buy the brand that could be serviced closest to me. They are both great motors but every great motor can sometimes have issues. Most issues might just be operator error and not the motors fault. Either way, you will eventually need service and/or parts. A good service department can make or break your ownership experience.
All things being equal, when you look at all the commercial boats down south, most of them have yamahas hanging on the rear. I think that really says something.
So there we were, 4 against 40, they were the toughest 4 I've ever seen