quote:
Originally posted by lwmweb:
My question (not well stated) was are they really worth using? My feeling is that they are questionable except in special situations where the planet has high modifiers. I am a finance type and always look at return on investment whether it is time or money. So what is my financial analysis of SEIV. Hey some things you do just for fun. 
It is simple really, when a planet has at least two high resources (say, above 110%), it pays to build monoliths instead of standard extraction facilities. If however planet has only one high resource, build extractor for that resource - it is most cost effective. The only exception from this is when you build multiple value improvements on planet (yes, they are cumulative) - in that case go for monoliths, simply because all resources (except those that have 0% value) will rise and make your investment pay off.
Of course, if you were in an emergency for a specific resource, you would go for extractors for that resource because they are cheaper and faster to build.