Nos's PM will be good/bad however you look at it, as he told me the stoy once.
Looking at their site, the trailers look very slightly built with very small box sections and no regard to the forces involved or good engineering practice.(In my Opinion of course).
It also looks like somebody stole most of the rollers!!
I'd say don't do it, pick up a used rollercoaster and throw some new axles under it.
RIBBED For extra pleasure.
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