Not flying yet but ER tanks are installed. The tanks are beautiful and the installation was not difficult, though I don't think I would want to do it after the plane had been painted...
Yes, I have them in my 10. They are wonderful, especially to carry extra fuel for day trips to places that don't have fuel, an don't have to stop on the way back for fuel.
You can see them in my build log at mykitlog.com. Just search for Lussow in the name field. If you want to see them in person, I think you are only about an hour from me on I74...
I recently installed a set in a flying and painted -10. It's a really nice kit and nice to have the extra fuel when needed, especially in situations like Vic mentioned.