FasTrack should do just fine for an around-the-tree layout in a 4x8 space.
I only have room for a small circle around my tree, so am using regular Lionel O gauge tubular. Found a whole box of the stuff--mostly new--stored in the garage. It had been in that box for some 12 years, according to the date I wrote on the box when it was packed. It held up fine over many harsh winters and very hot summers in that less-than-ideal environment. Glad I coated it with WD40 before I store it.
The tubular track, which I screwed down to the circular platform, will do fine since I only plan to operate a short O gauge tinplate train around the tree this year. Besides, tinplate and tubular track is a nice nostalgic pairing.
