I have looked at spare magazines for my .40 subcompact and there are only two made for this gun. The ten round and the thirteen round.
Herein lies the dilemma. They are actually the 9 round and 12 round magazines. I have seen them advertised as 11 and 14, 9 and 12, 10 and 13.
The magazines having springs so tight you need a Russian weightlifter sitting on your thumb just to load 5. I don't think I have ever loaded them to capacity.
So I am asking, why is there such a discrepancy of numbers?
On a related note...
I went to the local gun shop last week and surprise, they had three 11 round subcompact magazines.

I got them home and tried them in my gun and they only went in about 3/4 inch. All three! I looked at the package and it said XD(
m). OK, tool on back and exchange them. The gunsmith was very apologetic and looked into the computer. He said they did have three and looked for them on the rack. He couldn't find them so he turned around to the shelf and found the magazines. XD .40 subcompact 10 round. Oh happy day!
I returned home and they fit. Great! started loading them up and couldn't get 7 rounds in them. WTF? Looked them over and the baseplate said 9mm! The packaging says 40 cal S&W, the mags were 9mm.
Returning to the gun store I left with a gift card because guess what, no mags.