The blocks I currently use to make 15/30 PMAGs are translucent and would look funny in a windowed mag however by changing the block material, I could make a black block that would blend with the mag body and contrast against the orange coil of the spring that shows the number of rounds remaining. Would anyone be interested in black 15/30 EMAGs or 15/30 windowed PMAGs using this black block?

I'd be interested in the EMAG more than the windowed PMAG. I really like the versatility of the EMAG, especially considering the different models of AR-variant rifles crawling out of the wood work these days (all having to be able to utilize STANAG mags). I'd personally hate to get something like a SCAR 16, and then not have access to magazines that consistently work (I've heard there were issues with SCARs trying to run PMAG-- might have been resolved by now, though, I doubt it since it seemed like it was a civilian-SCAR issue, not a magazine issue).