Well Well, I MAY have an ASP advantage. I work in a development environment where we use ASP, PHP, and now ASP.net abundantly.
The only thing I wish I could do in PHP that I can do is ASP is use Application functions of ASP. For example, in ASP I can have the Webserver automatically do something when a session times out. If anyone has a PHP alternative to this, let me know?
My general impression of ASP. Well, it's like having at least one hand behind your back. There are so many more possibilities with PHP than ASP. Some of the "things" are possible in ASP but you end up paying mega bucks to third-party components you usually have to install.
Also, arrays are just a nightmare in ASP.
Finally, the ASP community is even moving away from ASP for ASP.net which allows you to code in C# (resembles JAVA - probably ripped off ;-). C# has some nice refinements however. Basically, the bottom line is ASP is a dying scripting tool (was gonna say language but it's really just VBScript with a tiny bit of ASP stuff that makes VBScript work wioth IIS.)