Omnipod Questions

I am thinking about getting an omnipod soon. I have 2 questions though that I would love to have answered before I go any further. First, I live in the midwest and we sure do get hot here. Does insulin go bad because it does not have anything to keep it cool. I usually use my FRIO wallet to keep my pens cool so I do not know how insulin in a pod will do without my FRIO. Secondly I know that the pod is good for 72 hours. What if though you did not use all the insulin in the pod? Can I use the rest of it up? Can I restart it like a Dexcom sensor? Would love the feedback. Thanks!