Hi Ben,
Have a couple here you are welcome to borrow for a few weeks to see how you go.
CO2 is a great power source for its size, but expensive if you shoot a lot. CO2 is self regulating but temp sensitive, best to use them in summer. Moderate power available with modifications and can be quiet with a suppressor.
PCP is great but you need to have all the filling gear to go with it. They are expensive to buy and setup and unless you add a reg they can have a shot curve that takes some time to get used to. Heaps of power potential in the bigger bores, I have heard of multiple Reds shot with them on private land. Also the only legal way to hunt game with a pistol in NZ.
Springers are hard to shoot accurately, they are generally lower quality and the recoil takes some getting used to, power is also pretty limited.
Single stroke pneumatics are easy to shoot accurately and generally pretty quiet, but lack power.
Multi pumps are pretty good for accuracy, price and reasonable power. They come in a few different styles, the under pump like the Crosman 1322 or the over pump like the Zoraki. The main disadvantage is the pumping between each shot.
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