My question would be, is that 200 lbs per engine or 200 lbs for both when you switch between the 30 hp and 40 hp engines?
Honestly - I would go for the lighter version even if it is 200 lbs total. That is 200 lbs of cruising gear
you can put on board and not effect your performance. Twin 30 hp engines in a light cat are going to be plenty of power and the sailing performance benefits from the boat being lighter are going to be worth the lower power.
As for the sail drives, they are a fact of life on modern cruising catamarans. Make sure to take good care of them and they will be just fine on both the Volvo
and the Yanmar.
I would personally prefer Yanmars but would be curious about the Beta Marine
engine. The Betas have some interesting features. I would also want to compare weight between all three.
Enjoy your new boat and let me know if you make it down to Grenada!