I use Cardsaver I's then I put them into 4 pocket sheets and into binders. That way the cards are well protected but also in binders for convenient review. I use a clamshell style all poly binder by Unikeep which has both a very slim squared profile [useful for limited shelf space] and no open edges to snag sheets and bend cards.
http://www.unikeep.com/
For small cards, like strips or 1950 Bowman, I put them into the Cardsavers sideways, push them to the bottom, then cut the holders down so they fit into 9-pocket pages, then into the binders. Very efficient for storing the smaller stuff.
If I don't care about condition, I will put them in 9-pocket sheets and into the binders.
I also use their small binders for postcards, which I find very convenient, with their one-pocket sleeves.
Only drawback is that their thickest binder is 1.5", so a good sized set will take several. I am not a set guy, so I never find it to be a drawback, but I could see how it could be problematic.
They also have a really thin binder [half-inch], which I use with a 1 pocket sheet for the few large slabs I have, one per. Probably overkill but since I only have a few of them and they are really 'important' cards for my collection I figured it was worth it to protect and present them nicely.