I know of no good reason to not use Tomcat as a "production" server. Especially if your site uses JSP and/or servlets extensively, the extra steps involved in transferring request and response between IIS and Tomcat must surely be time consuming. When I moved a client's app from a Win3k-IIS-tomcat configuration to pure tomcat they reported better response times. As far as I am concerned the "dont use Tomcat for production" is just another annoying Java myth. Bill
Not so much a myth as good advise from the past that's become meaningless over time. Early Tomcat versions were quite slow compared to the commercial servers, especially when serving static content. Thus it was almost always better to host static content at say Apache and link that to Tomcat for dynamic content (or another servlet engine).