Why Sharkbites? They're expensive, they're bulky and you're not reducing the risk of leaks. I'd go buy a PEX crimper (cheap on ebay) and use copper crimp rings. The rings are cheap as well as PEX fittings. You can also get a "pocket crimper" which fits into small spaces. Another option is PEX clamps like most manufacturers use, but I'd use crimp rings. Using a crimper and the rings is easy and veryy foolproof and it's extremely unlikely you'll get a leak anywhere unless you are all thumbs. You could do a pressure test with air if you feel uncomfortable with your work or if you have an assistant available, have him/her slowly turn the water on just a little while you look for leaks and can shut it off quickly if needed.
PEX lines rarely get damaged from freezing and it's faucets, etc. that could be. But you should be winterizing each year anyway.
BTW, I recommend installing a master shutoff valve in an easily accessible location inside. That way you can quickly shut the water off for times you are out shopping or on a walk. Toilet valves have been known to leak. If doing extensive plumbing work, I also recommend a good pressure regulator inside like a Watts 263A along with a gauge.
