I haven’t. I’m local to the port, actually. But that’s a fair distance to the ship. If you’re staying more than one day it might be worth it to take advantage of the resort amenities. But if you’re coming in the afternoon before, weather could wipe out your ability to enjoy it.
Out of curiousity, have you looked at Ron Jon Caribe Resort? I was there a few years ago. Much smaller scale than Margaritaville, but within spitting distance to the port.