We are ready in our company to move everything to Python instead of C#, we are a consulting company and we usually write small projects in C# we don't do huge projects and our work is more based on complex mathematical models not complex software structures. So we believe IronPython is a good platform for us because it provides standard GUI functionality on windows and access to all of .Net libraries. 
I know Ironpython studio is not complete, and in fact I had a hard time adding my references but I was wondering if someone could list some of the pros and cons of this migration for us, considering Python code is easier to read by our clients and we usually deliver a proof-of-concept prototype instead of a full-functional code, our clients usually go ahead and implement the application themselves
The way you describe things, it sounds like you're company is switching to Python simple for the sake of Python.  Is there some specific reason you want to use Python?  Is a more dynamic language necessary?  Is the functional programming going to help you at all?  If you've got a perfectly good working set of tools in C#, why bother switching?
If you're set on switching, you may want to consider starting with standard Python unless you're specifically tied to the .NET libraries.  You can write cross platform GUIs using a number of different frameworks like wxPython, pyQt, etc.  That said, Visual Studio has a far superior GUI designer to just about any of the tools out there for creating Python windowed layouts.
Pros and cons of IronPython and IronPython Studio