Subject to your getting your NFA licencing and tax sorted, these are a good piece of kit.
I'm pretty sure they are a 1/2" UNF thread, if not that, then they are certainly similar or close to that, but for sure they screw onto the barrel.
They will reduce the noise down on a 10/22 to the point where (when used with somthing like Winchester subsonic) the action is the noisest thing as it cycles.
If you use a bolt action the hammer can be heard dropping and then there is a thwack as the bullet makes contact at the business end.
If you encounter a group of say 1/2 dozen rabbits, you can shoot them at one end of the string and then the other and unless the thwack startled them and they spook you are almost certain of at least a second shot.
If they are feeding they will often do that obliging sit bolt upright and sniff the air routine (AKA shoot-me
However I believe you may have state law or Game and Fish regulation in the US that may prevent you from using one for hunting, you would need to check with the relevant agencies where you reside.
With regard to accuracy I use a PH moderator (thats the term we use over here not a silencer) an a number of rifles it doesnt affect accuracy but can have an effect on the point of impact with some ammunition (ie you may need to re-zero)
In some cases I have heard of rifles loosing their accuracy when the muzzle has been threaded to accept the moderator. This has been with barrels that were chocked or heavy bull barrels that have gone mushy and where the stresses have all moved at the muzzel when it has been machined.