Hi guys & gals
I am using Kato Ho track with my On30 trains !
they run great so far.
granted these layouts are not permanent !
kato track has 19" radius , 21" radius, 24" radius, 26" radius, 28" radius, 31" radius .
there is a 16" radius ( maybe used for the two trollies Bach makes)
I hope this helps someone . KATO HO track has the built in road bed .