BizSpark aside, I think hosting costs/maintenance is much more. For a $20 512 Linode it would cost a hell of a lot more to run MVC.NET + MSSQL.
BizSpark aside, I think hosting costs/maintenance is much more. For a $20 512 Linode it would cost a hell of a lot more to run MVC.NET + MSSQL.
Even if they give you the licenses for free, it's much more expensive.
It's different to design a HA cluster that can sustain a minutes-long usage peak (due to a node going down for maintenance) than one that can sustain an hour-long outage of one of the nodes.
It all depends, in the end, on how the applications are designed to run - they are the ones that will decide how many servers you can take down at once. In any case, the shorter they are down, the better.
Consider a site with 3 front-facing web servers that are affected by a 0-day. If a server can be patched in 2 minutes, it will result in 6 minutes of 150% load on the servers not being maintained. If the patch takes an hour, you will have 3 hours of 150% workload. The internet user may not see the downtime, but you have to factor in the higher load. The best solution could be to use 4 or 5 servers instead of 3, but that would also increase your vulnerability window.