Keep a hold of it!
You keep a hold of that baby!
As an ex-employee of Glenmorangie in 1995 who received one of these I can tell you it's worth a lot more than £175, in fact if you look at whisky-online.com there's a bottle on there for sale at £899!!
Jojo is right though - it's only worth what someone is willing to pay.
As a slight aside I remember the day we all got them some people went straight across the road and sold them to the local shop for £50; I wish I had a bit more cash in those days - I would have bought them!