Very good!!!! The only thing I can see you having to worry about is your air hose freezing up. You might want to go buy a 1/2 air hose from lose so you air hose want freeze close when you are making snow.
Well you real don't need an air hose you can just use another air hose.... An air hose is just a hose like any other hose but are normally rated at 300 psi, but when running the snow gun you only need a hose that is rated for 40 psi (most garden hoses are rated for 150 psi) just use a 5/8 inch garden hose and you will be fine.. They are also alot cheaper....
^yeah, but make sure that if you buy a garden hose that the connections aren't cheap and use a simple flange to connect, otherwise it will leak and you'll lose a lot of pressure or just seal them up.