ideas on economical IWB mag carriers (S&W shield 9mm)?

I bought a IWB holster with a built in removable mag carrier. Bug Out Custom Holsters.

If you do a search on the internet you will find the general consensus is they are highly uncomfortable. I tried them myself and have to agree. Not enough surface area...they dig into your side.

__________________
Thirty characters. Exactly...

I absolutely agree. IWB for magazines is very uncomfortable. Well, the Shield is a small gun with a small magazine. I would recommend just getting a nylon belt-knife case and roll with that. It would be small and unobtrusive. They blend in well and are comfortable. I use these for Ruger LCP magazines and they are perfect.