As for using Mudbox it was great fun its extremely flexible as the level of detail is unbelievable, although this can also create problems as it can get very hard to limit yourself at a sensible level of detail. Once i had made my island at a sensible level of detail I exported it too a .ma file then imported it into Maya along with its texture. Once in Maya all the polygons edges had sharpened and I didn't have a clue how to fix it. When it came to fixing this issue i struggled to find a solution on the internet but it happened that one of my class mates had the same issue and it ended up being something as simple as softening the edges.
Below you can see some screen shots of the model in Mudbox as well as the import version into maya with the hard edges