I'm running the NH version of that set on K-Line Super Snap O-31 track thru two switches.... so far no derailment issues.... with one exception. If I run 4 cars (3 + 1 optional), everything is OK, if I add the 5th (3 + 2 optional) car I get a string-lining derailment. Seems like it's too much weight for a tight curve.... derails on the curves not at the switches. Disappointing, but I really like the set!
I use Fastrack for my main layout, but wanted something that looked a little more tinplate-ish for my tinplate layout.