Quite by accident, I discovered that I have been using Caboose #202S. I really believe it doesn't offer enough "throw" to keep the point rail pressed hard against the stock rail for good electrical contact. After all, they're HO.
I just bought #208S and will see how that works.
Also, anyone use a switch machine with 2" foam base? Don't know how the required long throw rod would work.
Thanks!