So for advanced water skiing, the MC is by far the better boat. By "advanced", I mean slalom skiing with a skilled skier who wants to be going >30MPH. The MC has an almost non-existant wake at that speed, and the back-end is planted in the water, so it won't get displaced by a strong skier. It also has ridiculous torque, so even the "bigger" strong skiers get pulled out of the water with no issues.
This is where the main advantages of the MC end though for the way we use our boats...
For beginner water skiers, the Yamaha can be kinder with take-off, as you can feather the throttles easier, and take off very, very slowly. As well, at any speed below 25 MPH, the wakes are fairly comparable in size. With that in mind, the Yamaha is always the better choice, as there are always lots of family members along for the ride to get all those action shots, and there is usually the requisite "stop and swim in the middle of the lake" break, which is way more fun on the Yamaha. The Yamaha is better with more people because the MC is mid-engine, so there is no open space, the more rearward seats are not useable during skiing because of the position of the ski pole (pretty much even with the driver).
For wakeboarding, at 13-21 MPH, the Yamaha throws a much bigger wake than the MC.
For entertaining, adult boat rides around the lake, trips across the lake for ice-cream, or day trips to another lake through the locks, the Yamaha is the clear winner, due to:
1. way more useable space
2. better seating and storage
3. v-hull on the Yamaha vs. almost flat hull on the MC
4. have you ever tried to reverse in a MC? good luck
So while for some people, it maybe not thinkable to use the Yamaha more than the vaunted MC, for the way we use our boats, it works out that way

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