Quote -  and a lot of people say luxrender gives them lots of crashes, which i would definitely like to avoid.

Pick any piece of 3D software and there will be a group of people who experience some crashes, for a lot of rasons, not always related to the software. Lux is very stable. The main reason for some crashes is to render images that are beyond the installaed amount of RAM in the machine. 

Physics-based rendering poses more demands on your machine.

Cheers 

Paolo

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