Their new medium sized model is better than the snubby IMO, just a hair more room and sits on my chest better crossbody. Not sure how the medium works for a Fanny Pack as I've never tried it.
Edit: you did list the medium haha
https://hillpeoplegear.com/Products/.../ProductID/184
IMO if you're going to stick with a G26 or J frame than the snubby kit bag is great but for a G48 or even G19 MOS the medium is the size to go with.
In my experience a G19 or G48 does fit in the snubby but depending on the sights you have it could get snagged by the zipper.