Now I will wait until someone makes conclusive tests over scanner use and robotic factories and provides us them
Or at least mathematical calculations. Hmm... perhaps I should do them myself. Actually, now that I think of it, it could be done by using a little program which counts amount of planets, their sizes (ie. amount of buildings), percentual amounts of every resources/planet and then concludes them with the multiplier when using scanners or factories (also considering the effect of converting excess resources to other resources). I have to think about this little more...