At a guess, the horrible finish is something for the "collector" market.
Arnold did occaisionally do oddball things aimed at them.
As a model (finish aside), its quite decent for its period. Arnold usually
made decent models. As for value, who knows; some things seem to go for
very silly money on Ebay.
It should run fine on normal N-gauge track, though if its been standing
unused for 15 years, the bearings may benefit from **tiny** quantities of
clock oil. Clean wheels with care (avoid agressive abrasives, they only
scratch which encourages more dirt).
I think you can still see the real ones operating in preservation.
Class Ce6/8 I
1'CC 1' or 2-6-6-2.
It is a "limited edition" version of their standard Swiss "Krokodil", but
produced in one limited run with real gold plating.
The gold doubled the purchase price!
I'm not an Arnold fan/collector so I don't know the year it was released but
somewhere about 1988-90 sounds about right.
There were other models; the DRG BR 95 (2-10-2t) and KPEV P4.2 (4-4-0) spring
to mind in other years.