I know there may be some, but I don't run into too many folks who want to convert to 3 rail operation once they have 2 rail equipment and a railroad to run their models on. It seems there is a growing trend toward 2 rail and that may be upsetting to dedicated 3 rail scale modelers. It shouldn't be...they have made a decision to accept the 3 rail track system and I have a seen a few very nice model railroads using 3 rail track. Whatever makes you happy.
When I was 10 years old and my Lionel Scout gave out, I switched to 2 rail American Flyer S Gauge and then onto HO in high school and 2 rail O in 1972,
Joe Foehrkolb