Wow, the price of that gun sure went up --- what did we pay for ours $70 ???
In any case, shooting it in the house against an impromptu backstop would be a no no as it would go right on through 1/2" plywood layers with no problem. I used to shoot the top cap on my chain link fence corner post to get a gong "tink" sound, until I put a hole in the casting (stacked 2 hits on the same spot and it was more than the metal could take). Lotsa dents on that corner post cap .....
The gun will reliably through and through rabbits and squirrels, it knocks them over as it is a heavy .22 caliber pellet at 950 fps (we don't shoot light .22 pellets as they go supersonic on us and that is NOISY, makes a crack sound that resembles a .22 bb cap going off.
The gun isn't quiet and since part of the noise is the air spring system inside the main tube there isn't any way to make it really quiet.
Rabbits get knocked over but sometimes get back up, squirrels fly off limbs and trunks but generally hit the ground running, but they do bleed out pretty quickly about half way up the next tree.