Just a note about the Sigma mags: the Sigma baseplate is not only shaped differently, but its also thicker (this is on the SW40VE ones, not the SW40F which is WAY thicker).

The Sigma baseplate from bottom to the top mics out at 0.263". The SD baseplate mics out at 0.244".

For me this is enough that the Sigma baseplate is just about bottoming out on my SD40VE before the mag catch engages. If I take a second to wiggle it a bit it'll catch, but it doesn't do so as effortlessly as the stock SD baseplates.

I personally wouldn't trust the mags with the Sigma baseplates to correctly seat if I had to change them at speed. As a result I wouldn't hesitate to carry a Sigma mag in the gun, but I wouldn't carry one on my belt as a potential reload mag until I'd switched out the baseplate to an SD one (or sanded down the Sigma plate a bit thinner).