I'm a little late to the S7 party, but I'm very happy with the Spigen Tough Armor case. My only hesitation was that Spigen doesn't seem to offer holsters for any of their cases. What I found is that the holster from the Platinum (Best Buy house brand) case/holster for the S6 is a perfect fit for the Tough Armor case for the S7. I'm pretty sure the Seidio Surface holster for the S6 would fit just as well.
I also found a holster offered by Encased, that they claim is specifically designed for the Tough Armor S7 case. What they sent me was labeled as being for the S6, and was a sloppy fit - especially the bottom corners of the holster that stick out way to far and are bound to get caught on things. I'm still waiting to hear back from them regarding this. It seems that rather than having holsters that are "specifically designed for" something, they have holsters that "could be used in a pinch" for various devices that are similarly sized.
I also found a holster offered by Encased, that they claim is specifically designed for the Tough Armor S7 case. What they sent me was labeled as being for the S6, and was a sloppy fit - especially the bottom corners of the holster that stick out way to far and are bound to get caught on things. I'm still waiting to hear back from them regarding this. It seems that rather than having holsters that are "specifically designed for" something, they have holsters that "could be used in a pinch" for various devices that are similarly sized.