[dvdcnl]

I read that a diesel needs to be run hard to keep it running good. The worst thing for it is to idle out of a marina, raise the sails and shut it down. It never gets up to temperature. That's bad for a gas engine but even worse for a diesel.

A diesel is supposed to get better fuel economy than gas. You need to consider how much the difference between diesel and gas will save you over the life of the engine and if the extra expense of the diesel engine would be worth it. If and when you sell the boat, how much will the diesel engine add to the value?