For a cheap fix, use Vinegar and water - I think 2 to 1 is the mixture suggestion. I like MAC cleaner for my personal brushes since it condition them and I've spent a ton of $ on my huge brush collection (I use a brush to apply everything!).BTW, don't place your brushes upright after cleaning! Dry them by placing between a towl or paper towl and applying pressure, being careful not to be too rough; then LAY THEM DOWN on a paper towel to dry completely- you don't want any moisture to run down into the barrel.
I like MK Minerals but can't use them alone, unfortunately. I have to always consider protecting my face from free radicals, bacteria and sun here in So California so I use a sheer, waterproof foundation from SeneGence and powder lightly with the minerals.
Alimac made great points about choosing minerals (no talc, non-comedogenic, etc) and it sounds like the suggestion is one to check out.
hugs, kelly