Oh, the outboard world of today. You have the Tohatsu Mercury vs. the Mercury Mercury. Sorry to hear of your problems.
Funny, I grew up an OMC fan as my father had Evinrude and my uncle had Mercury. Them have Mercruiser and then Volvo I/O's before getting to diesels. However, the only outboards I've personally owned are the Yamaha 300's on a boat we have for employee usage. When we bought the CC with them 7 years ago, we were adamant for Yamaha, but not for the 350's which were a mess. Now in the large horsepower ranges we would feel compelled to go Mercury. Yamaha has had a lot of problems, but worse, they've made no improvements to address them. It's like they just stopped. They've got the 425 hp offshore, a totally new and different design. They appear to have given up on the 350 and dropped it. It appears to me that if you buy 300 hp or below you're buying the same engines you would have years ago. Meanwhile, Mercury has addressed issues while also expanding their lines. They have V12's of 500 and 600 hp. They confuse me with 4 different lines but their Sea Pro designed for commercial use is extremely popular for those users. They have their jet outboards and their diesel, a 175 hp two stroke. Their diesel only has a 50 lb. weight penalty versus their gas model. Oh, and a 5 hp propane.
Now, I've come to a conclusion and it also applies to the Tohatsu engines. Mercury, and this only applies to the engines they build, not the OP's, is the only marine engine builder whose primary business is building marine engines, for whom that is their sole focus. Boats to them are simply to sell engines, but no tractor engines, no motorcycles, on four wheelers, no airplanes, no other businesses. It seems to be during the last few years, the others have given attention to their other businesses and not to the marine engines.
I never thought I'd be tempted to buy a Mercury but when we replace our CC, we will. On the other hand, I'd never buy a Mercury by Tohatsu, having seen the problems. The challenge is I'm not sure what I'd buy instead.