These are the latest bunch. The one on the left is a bent poly side shooter. Bands or tubes OTF or TTF with quick change slots. It's a left hand hold model.
The other is a prototype I'm calling "fogettaboutit". Because it's a pinky ring shooter. It needs a little tweaking but I think it can be sorted out. Hat tip to Darrin Glenn Cook for the idea. The band attachment is done by cutting a small slit in the band then securing the hardware together.