If you have no traffic and do not have the flag always on checked (does not work in free site, only in standard) your site will "die" and need to be restarted, think that it will be needing a IIS start everytime.
If you have a live site in Azure that is not so popular it is important to set the Always on flag.
I have done some testing with lastest episerver on Amazon and Azure. It is easy and nice. But the performance is bad on first request. Don't think it has anything to do with episerver, but maybe somebody here knows the answer.
There is no traffic on my demo site to keep it alive. The first request is very slow, after first request the response is good.
Even if i just use a hello world html file (no database or image).