If your willing to spend the upfront cost for a centrifuge they are great.
early when I just started experimenting with the oil I tried filtering it with pumps.the pumps would work ok for 5-10 minutes than die from pumping the thick oil through a filter.So I saved up and got a bowl and a motor from simple centrifuge and built a stand for it all.
I can change the filtering just by adjusting a valve.Right now I run the oil through at full bore to remove the water, then I run it through a second time at like 1.5 gallons per hour to remove everything larger than say .5 micron.
after im done the oil is like one or two shades lighter but it pours like new oil.Before it gets cleaned it tends to flow a bit slower,like its full of sludge, which it is.
just the amount of crap left in the bowl after the full bore run through is amazing.in five gallons of engine oil I tend to pull out 1-2 lbs of GUNK.I haven't measured it but scooping some up with you finger and that stuff is heavy.