I do the 7 and 5 gallon containers along with several cases of 1 L bottles. I believe Doug mentioned the chance of large containers getting contaminated or container failure as one reason not to keep all your water in one or two 55 gallon drums. I like the idea of circulating it via hookups to culinary, though, since that should solve the contamination potential.

I stack by aquatainers on a palette in the unfinished basement. No real need for shelving.