The tool chest works well as long as the depth of the various drawers meets your needs. The locking aspect isn't that big a deal as the thief can just roll it right out - at least you don't have to worry about him hurting his back. I've seen commercial studios use these.

You probably need some sort of divider/padding to keep some items from tipping when the drawer is open or closed.

But I use plastic containers in a closed cabinet. I try to use the smaller sizes so that a) nothing is on top of something else in any one container and b) the contents of each container is relatively consistent (i.e. "folding cameras", "Olympus OM"). The containers are stacked on a shelf, but only 2 or 3 high.