True RC says these "ARE PRETTY CHEAP AND WHEN PREPARED PROPERLY, WILL LIMIT THE DESTRUCTIVE FORCE OF A LIPO FIRE IF ONE WAS TO HAPPEN."

Okay. I happen to have one of these. What is meant by "prepared properly?"

From what I have read, most people install some sort of padding inside the ammo box to protect the batteries from flopping around during transport.

Woodie

Some also recommend a vent hole to let gas escape in the event of fire. The cases are water tight.

Okay. So maybe a foam liner and a baffled hole for the charge connectors.

Okay, here's what I came up with.
I drilled a 3/4" cable access hole near the bottom front as shown in one of the photos.
I cut some styrofoam slabs for liner. The foam is held on with a few strips of double-sided tape.

looks good, now paint the box and put some 'scare' stickers on it and people will ask where you got the commercial battery box. You can tell them Uncle Sam built it for you :-)

Woodie