I have been running my 17.4 with the beavertail for almost two years now. As much as I like the Glock I had to go to the bevertail because 50 rounds was enough to start the blood flowing. With my 20/21 I never had that problem, the extra 5% in all dimensions was enough to keep me unscathed. That said, I bought a 17 MOS, as a testbed for optics, the got bit by the Roland bug. Now my optics testbed is to be chopped to 19 length, and if I am going to do that I might as well get the trigger guard undercut, so the finger grooves are off kilter and will have to come off. So I might as well, have Dave Bowie add a beavertail.
pat