the only issue I have with the pre-made walls is there not tall enough I need 10"-11" in height so usually make my own.
I use 1" blue hard foam board wish the so called big box stores would stock the 1/2" foam boards too.
how flexible are those flexi-walls was always curious about that.
I did get to scenic express and at least the seam sealers are tall enough for my needs.
hot summer in southwest deserts is a grand time to work on train scenery!!