I bought my Gerstner tool box back in the 1960s when I was an apprentice, I bought the biggest one they made at that time and filled it, as I was unmarried at the time and had bucks to spare! I think the box cost only $76 at that time, when journeyman wages were about $5 per hour. Mine is made of walnut and is still pretty. I later bought a lower unit to go with it. One thing I did with the upper box was to make a divider of 3/8" thick hard white felt, carefully cut out to separate all my micrometers, so one drawer can safely store all my mikes to 6" and my depth mike with it's rods without getting them dinged up, and also all the standards and adjusting wrenches are provided space nested in the felt.
I never liked metal boxes, in the shop that I apprenticed in and worked in as a journeyman, perhaps 1/3 of the men had wood boxes, the rest metal, and a rough shop, perhaps metal is the better choice, being more durable, but I think fine tools are more at home in wood; the old timers said that metal boxes can sweat and your tools can rust and that there is much less tendency for this to happen in wood.