I bought the mega-starter box back in January. That included the "normal" size starter set that's still for sale on their site now, plus a bonus booster of three additional infantry sprues for each army.
The bonus sprues came in the form of Warlord packing the starter box with one each of their Union and Confederate brigade boxes along side twelve loose sprues for each army, for a total of fifteen sprues for each army.
The sprues that come in the smaller brigade boxes are completely identical to the sprues that come in the starter sets.
Same exact mold, same exact blue and gray plastic.
With the starter set available now you get twelve of those sprues for each army which makes a grand total of 24 five-stand battalions. In the brigade box expansions you get three sprues which makes three five-stand battalions.
The other boxes like the Zouaves, Iron Brigade, Cavalry, Skirmishers, etc. appear to be being produced in both metal and resin. They originally wanted to do all of those expansions in resin but they had productions issues which compelled them to produce many of them in metal instead. Warlord went so far as to put notification labels on the outside of the boxes so that you would know about the change as soon as you received it.
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