Thanks. I made a 16k one that stores almost all my important items that I have in pretty big numbers (1.5k redstone, 1k iron, 1k copper, and other stuff that I have hundreds of) along with important stuff like ender pearls and such. Fits quite nicely. Will make a few extra 4k and 1k drives for other misc items.
I found that a 1k drive works quite nicely for storing potions.