I've owned the 22TCM and 5.7 in pistols, and the 5.7 in rifle. Like most handgun cartridges, out of a rifle, there are a lot of other options which are better suited, more versatile, greater component supply, etc.
Getting a large shank Savage in any cartridge under the sun isn't a real challenge; just takes money for a barrel, bolt head, and mag box, and you have access to any cartridge within the action length.
My frustration with the 5.7 was brass supply. For its performance, it's a lot of work running down brass, and it's often frustrating to waste time looking for brass in the grass instead of hunting or shooting. Getting performance barely better than 22wmr or 17HMR, and lesser than 22H just didn't make a lot of sense to me, so I sold the rifle, and the pistol.
Brass supply for the 22 TCM, of course, is inundating, but for the performance, the same hunt for brass is annoying, as the consequence is cutting, trimming, annealing, necking, reaming & turning. Some guys get away without reaming & turning, but I prefer to have consistent neck tension, and I've seen far too much variation in wall thickness to be content just necking down. In a rifle, you're talking about a blocked magazine in a short action, with a 223rem bolt face - why not simply use a 223rem? That's the question I asked myself when I bailed on my 22 TCM companion rifle project. 221 Fireball or Hornet are better options as well, and the 221 brass is more readily available than factory TCM brass, OR can be made in the same method from 223rem.
If a guy is set on "something different," then I'd get a 221 Fireball or TCM, and skip the 5.7. The 5.7's a little hotter, but access to brass isn't certain.
