Dave,
I chartered the FP in the Abacos and I have chartered Moorings 4000's in the BVI several times. I would say that both are comparable boats as far as ease of operation. There were only two of us on board and we had no issues with either. I haven't seen the newer model Moorings boat, the last I was on was model year 2021/2022 or so. I think this will come down to a personal choice for you as well as your budget. Unless one has a considerable upside in amenities (i.e. refrigeration or water maker), there won't be that much difference to make me choose one over the other. If you like the bow door on the M4000, that would be the only other significant difference. I haven't seen the M4200 as referenced above, but it may be worth looking at.
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