Many thoughtful replies, thanks.

The idea of the suppressed pellet rifle is to have an ultra-quiet hunting tool to give minimum notice of hunting going on to critters and people. Staying subsonic, or under about 1,050 FPS, is aided by design using lead pellets and a suppressor. Several articles indicated Olympic pellet rifles shoot about 500-600 FPS maximum for greatest accuracy.

Like a 22, the ammo is quite cheap which allows for lots of skill-building practice. Unlike a 22, the pellet will not travel a mile if it is shot without a backstop, giving more safe shot-taking flexibility.

Each pellet is also quite small so you can carry a lot, there is some variety in sizes and shapes, and if you wanted you could pour your own lead pellets. And, of course, you pump these guns rather than percussing gun powder, so your "propellant" supply is essentially infinite and free.

CA hunting regs authorize pellet rifles shooting greater than .20 calibre for turkey, and most everything short of "big game," [such as beer, deer, elk, and pigs]. Unlike crossbows, pellet guns are not considered firearms and are neither rimfire or centerfire, so restrictions on the possession or use of such items do not apply; this gives pellet rifles a potentially very wide area of use.