Re: wich 22lr to practice?
I think that with the .22LR, unless there's something wrong with the rifle, the accuracy is in the cartridge. I think that when things go wrong, it's usually involved somehow with the barrel's crown.
I think that the CZ is the Cadillac (real nice but ya gotta treat it decent), the Savage is the F150 Pickup Truck (hauls the mail whatever the weather), the 10/22 is the Corvette (fast, but it eats a lot of gas), and the Marlin is the Buick Sedan (nicer than average).
I zero at 50yd, shoot 100yd for a challenge, don't shoot much beyond 100yd, and only go beyond 200yd once in a blue moon.
I'd shoot longer distances more often if I was shooting C/F at extended distances. These days, I'm not.
Pretty much all my comp is FV200 these days. I can R/F Sim that with the same target at 100yd pretty effectively.
In fact, I wonder if that might not make for a pretty decent event all by itself.
Greg