P94S.
As you know the 10 shot is metal so I guess they made it from steel for a reason, perhaps the plastic they used for the five shot was not strong enough.
As it is the 10 shot tends to need tweaking to get the rounds to feed as the metal ears spring back after pressing and cause poor feeding.
Could be why. It's why I'm not accepting any money until I can test the magazines myself.
Not sure what plastic the 5 shot mag is made from. I think the rounds stack alternately inside it rather than one exactly on top of the other - in the latter case I could increase the wall thickness but let's see how the prototypes turn out. I'm also not sure what length the spring is in the 10 shot as I can't get mine apart