This is the info I got from Dillster about keyshot

It really all depends on the amount of RAM on your computer.
This from the Keyshot product description:

Since KeyShot is CPU-based, any imported data is stored in RAM – not the video card. This allows KeyShot to handle extremely large data sets. There are no restrictions on the size of the data set as long as the computer has enough memory available. KeyShot is highly optimized which makes it possible to work with models with tens of millions of polygons even on a laptop.

Anyway, in reality Keyshot for me chokes on about 50 million polys. It can either just crash, or run too slowly for practical use. If I really want to try pushing my luck, sending Fibermesh over in generous amounts kills Keyshot.
My desktop is a decent gaming spec machine, but I know people with higher spec machines running Keyshot with 80+ million polys no problem. So yes it really does depend on the machine.

============================================================ 

The Artist that will fight for decades to conquer their media.
Even if you never know their name ,your know their Art.
Dark Sphere Mage Vengeance