Which Dealer is closest to you?
Some guys have 'saved' $500 only to now have to deal with a Dealer or Dealer network that is an hour or hours away, versus dealing with one minutes away. But also see below.
What is their reputation, outside of the brand?
What's their Better Business Bureau reputation? What is their word-on-the-street reputation? Sometimes purchase co$t alone, nor service cost-per-hour alone, is NOT an arbiter of the value that you will receive. I know of a local Nissan Dealer where sure, you can buy the OB cheaper somewhere else, but no one backs his motors better than he does ... including offering loaner OBs for when you may need service.
And when paying for that service, I'd rather pay $90 and get charged for 3-hours service and have it (1) fixed correctly the first time, (2) not have to go back and (3) also have them assess what else should be done then & there to have a reliable motor ... than to pay $70 an hour for 2-hours service and then have problems. This Summer my friend's V6 Mercury was showing signs of overheating, so I asked when was the impeller and thermostats last done? Owner of said OB was adamant that they were done not 2-years ago. Didn't make sense to me, so I used up one of my day's off (where I could have been fishing) to go with him over to his boat (an hour the complete other way from my own boat) only to look the OB over and pull the t-stat pocket and determine that in fact that the t-stats were corroded closed and were NOT serviced the last time that the full waterpump service was done.
Now what Dealer doesn't service BOTH items at the same time, on a large V6 OB motor used expressly in saltwater? Answer - the $70/hour one. Their excuse?
"Well, you only told me to change the waterpump." Are you kidding me? An on-the-surface more expensive Merc OB service shop I would have sent him to, would have said,
"Hey buddy, it's your motor, but in our experience with these motors, it is foolish to do one without the other."
A few other examples ...
I know of a local Honda Dealer who will 'not' service your OB motor is you did not buy it from him. Yeah, yeah, yeah ... I know that violates his terms of agreement with that OB maker, but what he will tell you when you go in there, say in April, is
"Well, I'm really busy getting my current customer's boats ready ... so bring it back in late June or July when they're all in the water." And then IF you went back there then, he'd have another excuse why it would take him weeks to get to it and would likely tell you to come back again in the Winter. And if they ever did take the job and accept the boat ... days would be weeks and weeks would be months! This happened to a good friend of mine and he had to initiate court action to get his boat back from the Dealer ... and not only was it not done, but he paid far too much $$ for what work was allegedly done ...
In one case I had with a new-to-me used V6 OB, I resisted going to the local expert, as they were charging a good $40 more per hour than the other guys around. Well after one of the cheaper guys fooled around with it for hours - and tried to just swap out parts (I stopped him ...) and it still wasn't right, I finally broke down and brought it to the expert, luckily by water as the boat was running, just not up to full power potential. He tied it to the dock and right there - and by ear - immediately and correctly diagnosed what the problem was. A simple $40 part and 1-hour on-water-service call fee (higher rate) later ... and I was back on the water ... chagrined and humbled
- but I also sure learned a valuable lesson! Which I don't mind sharing ...
Back to those OBs
If it were me the there was a good local Dealer I'd buy the Tohatsu. If I were to buy an OB tomorrow, Yamsters would easily be #3 or #4 down on my list. And yes, that Tohatsu spools up more RPMs, as that is where it develops those 5 more horsepower. No biggie, all OBs are sized/rated in such a manner like that.