I have Blade-tech, Side-Armor, and Comp-Tac.
Between those my favorite maker is by far Comp-tac.
The C-tac is imho the best holster, and I personally own seven of them.
The reason is that it is important for me to be able to tuck in my shirt over my gun and the C-tac has worked wonders for me. It conceals even an FN 5.7 under a tucked shirt for me with no cover garment, just a t-shirt and shorts.
Also they hold the gun securely.
As for mag holders I can't help you because I only use them for competition and don't use them for CCW. I just make sure my pocket is free of lint before I stick my back-up mag in there. YMMV
Good luck with your decision. Before you buy get alot of people's opinion and only buy one holster per make till you know what will work for you and your intended carry methods. Lots of people prefer different holster makes for different types of concealment options. Good luck finding what works for you, it is a trial and error process!!!
DON'T GIVE UP!!!