I have been using the WSI Import Tester from AspDotNetStorefront for some time when testing out new XML messages or just trying to figure out some functionality and always wished I could save the connection settings and reload XML test cases more easily.
This desire has grown into the build of an entirely new Windows Client that does everything I need. I suspect there are others that would like something similar so I intend to release the program for free to anyone that asks for it.
It is now ready – you can read all about what it does on the WSI Client product page along with a link on how to download a copy for free.