Is the base model good enough for what I want?

[ntsapp3]

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[ntsapp3]

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[mmk]

Since you are not a pro, I guess it will do just fine. If you use your programs under Windows, search google to find how to soft-mod your drivers, such that your X1600 video card will be seen by windows as a FireGL. Rendering will be much improved by the FireGL drivers.
If you plan on doing LOTS of rendering you might consider the 256MB version. Search some reviews for ati X1600....