well that simple update may make previous design obsolete....
but err.....
advantages to the previous design:
1. whichever is already in stock + production = speed.
2. tested already. there is no jamming.
version 2 however, requires some R&D and testing......
no good if the spring mechanism jams because the cartridge
is too long. it becomes a bit too unpredictable.
P90 cartridges were perfected already with alignment of 2 layers
of ammo i think......
but if to combine multiple cartridges.......
quite a risk but i think it's possible..............