It is a fair point to make. I could say Mac sucks and Windows is a 'super-system' because I simply am able to use Windows to better effect. The results and productivity I would get from a Windows system would be a reflection of my experience with it; therefore we can assume that if your inexperienced with Apache would lead to poor productivity and implementation and knowing IIS well you would get better results with IIS.
Don't worry about Manip.
Apache doesn't scale as good as IIS. That's for sure. Nobody who has credibility would say that Apache is faster than IIS or can scale better than IIS. Some just like to say something is better because they read that it is open source.
For your needs, probably IIS or another server is better. There are servers which probably scale even better than IIS.
Perl and PHP are jokes compared to Asp.net or J2EE today of course, because as you mentioned there is no debugging, tracing and many more other important features. But still PHP and Perl have values, lots of tutorials, easy to learn, start developing.... Learning ASP.Net and J2EE requires more initial investment then PHP. PHP, ASP, Perl are the old development methodologies, but those old methodologies have lots of legacy code around.
But still for many, Apache is a good choice. You have so many options, modules, and tutorials on the web. All of these also add a lot of value to Apache. Overall IIS seems to be a better solution for your case.