Hmm. Here's what I say about various programs:
Photoshop - for 2D graphics only. No (good) 3D capabilities, none without special plugins.
*Infini-D - the most user-friendly 3D program out there. That's what I use, and I self-taught me a great deal of what I know about it. Unfortunately, it's been discontinued (I think). It was last being sold my MetaCreations (http://www.metacreations.com) but they've merged it with RayDream to form Carrara...
Carrara - great features, mediocre interface (in ease of use and, all I can say is how it is for me), BUGGY AS HECK. Avoid, at least for now.
*Bryce 4 - THE program for landscapes, not great for ships. Another 3D program is almost required to render ships in Bryce; you'd make the shapes in another and export to Bryce. Very primitive modelling (place things like spheres, cones, cylinders, that's about it).
RayDream (any) - I don't think it's very intuitive.
Mechanisto - ick ick ick! Not user-friendly, and it doesn't make as good stuff as the others.
That's my list with my comments. I hope it helps.
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