I only have the dimensions of the metal ones, but in side by side photos they look at be the same as the plastic. Both hold thirty rounds. As I said in another thread, the Djiti boxes, both metal and plastic, are just plain wrong. Noticeably so.
That is true. But now that space is taken up by three fifty round hot boxes - a much better use of the space as the rounds go into the boxes already linked together. This shot from a BFIST interior shows that the hot boxes actually go under there in their soft cases.
I plan to do the soft cases separately from Milliput. If you don’t know this thread, you may find it interesting: