I use Vue but I've not used it to make maps.

I used to make some in Bryce though and in my opinion, Vue trumps Bryce in so many ways!

If you're not sure, you can grab Vue Pioneer here - http://www.cornucopia3d.com/pioneer/?affid=3222153 It's FREE!!! If you get on well with it, then the Fantasy or Sci-Fi would be ideal.

(Although I think the only difference between Pioneer and one of the T-Packs: the Fantasy, Fairytale or Sci-fi is that you get to use the objects in your scenes - but if you only want a map with mountains and sea etc then Pioneer could be all you need!)