OK I am setting up my WVO system and am still undecided on my filtering system, Main filter and on car. I guess it is a toss up between the bag style filters and the drop in cylinders. I have a couple questions though. First off how many microns are those cylinder water filters they sell at wall mart for water. they are 3 for $7 so if I coould work those into the system that would cut costs. Also I had an Ide, Mcmaster sells a screen sampler kit in which you can buy 10 6"X6" stainless screens ranging from 18X18 to 60X60 mesh size (openings per linear inch) (PN 92405T15) or ranging from 70X70 to 500 X500 (PN 92405T17) I was thinking these screens could be setup in series to filter alot of the greae, I figure the 500X500 would get down into particulates then just finish it off with a 5 micron poly filter.The stainless screen could probably be easily cleaned to be used over and over. I'm just throwing stuff out there I could be totally off on this but thats why I am getting some of your opinions.