I went from 6 movable (if you are King KONG) tool boxes to 2 Rollaround,s 6 yers ago. best money I ever spent. I can outrun any one holding one of those.I can tell if something is missing at the end of the day. How many tools went down the street after a project was dome? Lots, I think. I have left tools on the floor after some dash work, gone forever. I can only hope that the new home is good to them. something sad about watching the favorite pair OF vice GRIPS SLIDE DOWN THE STREET AFTER A CAR OR TRUCK LEAVES THE DRIVE WAY, aH, HELPING OTHERS, SO MUCH FUN. My Buddy wants to know why I let the Jack down so fast st the end of the day, that drop will shake loose things left on the frame. And put them on the floor where I can retrive it.I remember cutting lots of Rigid foam at work. Tool box told you when a wrench was missing. A hole was looking back at you.Air planes don't play well with loose bits floating around in side places they don't belong in. Pilots don't like playing catch at 500 MPH either. Missing sockets are a pet peeve of mine, always the 1/2 or 7/16 for some reason. 12MM and 10MM if it was modern stuff. Must be a thing with the manuf. Now I have a cart. Put stuff on the cart and save running back to the roll around. Parts go on the cart too. Now I need another cart...does it ever end?