I used the silver pen on my new z-scale layout to avoid soldering each rail joint and it worked great. I have no drop in voltage at all. I also used the silver pen and the carbon paint on rail joints of my backyard garden railway in some locations with great results also.
That is awesome!! The Carbon Paint and the Silver Pen are very popular with railroad enthusiasts. Thank you for taking the time to leave a review, it will help others who might be searching for a product for a similar application. Enjoy your trains!