Never even thought about needing a grain mill.
Not a fan of the Berkey company, they don't stand by their product. They have had quite a few defective filters go out in the past few years and luckily they will exchange them if you perform a non conclusive test(I ran this test when I first put my filter together and later the filters failed) on them and pay a fee.
You pay a premium price and people are betting their lives on them; but you definitely aren't always getting what you paid for.
I'm curious how many GPH it puts out. Assuming 50 gallons per day(24hrs) like it claims, that's no better than the travel Berkey only with a larger holding capacity. Plus, the travel Berkey could do more GPH with two filters than the Doulton LP-5 with 5. I definitely want to know more as I like the Doulton better for a few reasons, but if it's no better than the travel Berkey, I may choose the Berkey instead.I bought some of these Water Filtration Systems. World's Leading Water Treatment Technologies
pretty much the exact same thing, different company. (cheaper too!)
Portable Gravity Fed Water Filters. British Berkefeld/Doulton