Hey everyone,
I've got a grip design that's ready for beta testing.
It is only ~10 degrees off from perfectly vertical, so the hole for the grip screw would normally end up right in the middle of the backstrap. To get around this, I made the backstrap a separate component that is pressed into the front of the grip after being screwed onto the receiver. This also allows you to easily make the grip two-tone or potentially print the rear in a firm rubbery material for extra comfort.
I just printed the prototypes with plain old PLA. ASA should work fine.