I wrote a blog-post about it, you can find it here
In my conclusion I say:
Conlusion
If I have to choose for web applications than the express edition wins easily. The build in webserver, the graphical designer with split screen functionality and javascript debugging just make it too good.
If you think you really need to work with a database from within the IDE than also SharpDevelop is not for you. If you want to create a windows forms or console application both will work fine, if you want to build these applications more seriously and use a source control system, static code analysis and stylecop from the IDE you need SharpDevelop !
If the express editions would allow third party extensibility (Resharper) and solve my little annoyances, it would be number one.
If SharpDevelop would get a resharper add-in, a graphical designer for web pages and a build in web server, it would be number one.