You carry FOUR spare mags?
I'm gonna go out on a limb and guess that two of those are for the XD and the other two are for the Baby Eagle...right?
IMHO, if I were to carry a pair of autos, they would both be of the same maker. For instance, I would tote a Glock 22/27 combo...or an XD full size/compact combo or even an M&P full size/compact combo. Thataway, magazine compatability is not an issue. What are you gonna do when under stress, you try to shove that Baby Eagle mag into that XD?
And a spare mag for a matched combo should be the full size. You can put a full size in a compact frame, but you can't put a compact mag in a fullsize frame. My backup mag for my M&P compact is a 17rd full size M&P mag.
I carry at least once speed strip reload for my BUG (S&W 49 bodyguard). I've also been carrying a speed loader full of CCI shot for snakes on the family ranch.