JMOfartO:
In my limited experience I found Pro-Mags to be iffy.. I will say ProMag has great Customer Service as they replaced a new crappy HiPoint 995 carbine mag with a new one, no sweat, and even sent me a free dual mag holder for my trouble. (I originally bought two new Pro-mags, and one was perfect right out of the plastic wrap, and the second was terrible.)
Never heard of a bad MecGar... Period.
Now having been fair with ProMag I'm of the opinion that there are only two types of magazines I would personally buy for use in any firearm of mine..
1. Factory
2. MecGar
If you have ProMags and they have worked for you, great.. But if a person interested would "google" the subject, or use the "search" function on any firearm forum betcha' the majority of posts found would be negative.
It always amazes me that someone would spend the money on a (what I consider) a top quality firearm, such as a Sig, and then stuff a questionable aftermarket mag in it to save money. That logic escapes me.
If you stick to factory mags, or MecGar's you will be better served.
But, I'm just an opinionated old fart, so your mileage on this subject may vary.
Best Wishes,
Jesse
P.S. If you're laughing at the HiPoint 995 9mm carbine it means you've probably never owned or fired one.