Testing it what way? On the unit testing or the user interface level? Because the former clearly belongs on SO, and questions regarding the latter have very good chances to live on SO in my experience,e ven if they aren't 110% programming related as such.
If you have questions in the field, I'd say it's best to simply go ahead and ask them. Nothing worse can happen than that they get closed - no real harm done, and people will have it easier to voice their opinions when they have something to look at.
I personally would love to see such questions on SO proper, and not a SE spin-off. (That's just one man's opinion, though.)
Questions tagged Unit-Testing and testing