Why not write server code for Windows? I fail to see a major reason that would stop one from doing that. Actually, its a pretty good, well supported and documented and stable platform.
It means that if you ever need to scale up, you'll have to buy more licenses. It prohibits unlimited, automatic scaling.
It's also the once a month embarassing ordeal with sites being down due to server reboots after another round of Windows Update.
I deploy lots of stuff to Windows-servers, but I can see why some people would avoid it if they can.
Also, AWS, Azure and AppHarbor have takem the license problem out of the way.
I hope that this is just the initial phase of the company (although not too initial since you need 70 instances) and that you will get to a better margin along the way. Otherwise ANY bump you hit road ahead will break you.
Competing on a market that relies entirely on price is a death sentence, unless of course this is your plan.
Sure. For some values of unlimited it's purely an academic question. But if you can scale automatically to handle double load (which is a more real concern) chances are you can scale further without any other changes.
And yes, AWS, Azure and AppHarbour all have some of the licensing issues handled for you, but that can also be clearly seen when faced with the costs.
Again, I' not saying that nobody should ever use a Windows server for anything. I use it myself. I just say that I can see several reasons why people would chose to avoid it.
If you don't look at the big picture costs than you lose out on a lot of options.
There's other ways of patching servers besides all-at-once...