So I received a loop of 30" radius and a pack of 10" straights from MTH today. First off, they come in a blister pack, not a box like S-Helper. Slightly disappointed not to get a box, but whatever.
Put my Lionel SD70ACe it to see the overhang and how far the pilot sticks out, etc. Not bad, the middle of the knuck couplers seem to hover over the outside rail.
I'll add some more pictures later when I see how my well cars and auto carriers navigate these curves. If anyone has any pics of this S-Trax, please add to this thread!
Martin