They used to use the 570 Macs in Rarotonga as dive boats. All of them got retired due to splits in the hulls I believe. All that flexing had to come with a downside.
This might not be an issue in a boat that only gets used a few times a year, but when they were used multiple times a day, every day, the flaws really showed themselves.
I've used them a few times, and they are definitely wet, require a lot of HP for the hull length, and ride poorly compared to a well designed fiberglass or alloy hull.
Cannot comment on the smaller models, as I've not used them.
We exclusively beach launch, and you'd be surprised the size of some boats people launch single handedly with the club tractor.
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