[mattmanser]

I wouldn't lose sleep over performance problems. C#'s much faster than most of the other languages. Most of the ASP.Net MVC sites I've written have sub-50ms server responses even on tiny VPSes.

One of my old employers had 100s of installs of its VBscript, then ASP.Net, program, with a complicated salesforce-esque application that clients could customize themselves with extra code, so there was a wide range of code written by programmers of wildly differing ability. And they did all sorts of crazy stuff.

Almost all performance problems were SQL related.

In the 3 or 4 years I was there we had a bug with IIS once, some crazy specific thing, I can't remember it exactly but it would be like if you'd chose a very particular and obscure variable name and the value passed via query string was this one very particular value it would cause that thread to hang. Even that was fairly trivial to identify because a google search brought up an MSDN.

And when we were genuinely stuck by then we had some sort of partner status and could phone them up. When we were using silverlight when it first came out our technical director actually ended up chatting to one of their core programmers about a specific bug. I seem to remember this only happening with silverlight and with a very obscure tech we were using (some sort of strange clientside control that IE6 had that you wrote in vbscript that no-one really used that I honestly can't remember the name of now).