Shytalkz, your misreading that.
Sky+ is free, there is no charge to use the features of the sky+ box for sky TV subscribers.
This includes the lowst packages, NOT just the movies/sport packages.
AFAIK there is no other reason to have the sky+ box but to watch sky tv and in which case you would be a sky tv subsciber & enttiled to free use of the sky+ box.
Of course you often pay for the box, unless your a new subscriber & then they may give it away.
If you are no longer a sky subscriber then the sky+ box will revert to a freesat box enabling you to receive the free channels. The PVR features will no longer work.
Personally I would not touch an Amstrad box with a bargepole, as for the refurb it my be posible at a later date to get it replaced under warranty with a new one (AFAIK many engineers prefer to only swap out with a new one to save having to go back again).
I got my pace V3 box replaced a month+ ago just before the warranty ran out because it went doodah on me. the engineer left a brand new one
If the OP has not already got a friend on sky & has not already quoted the introduce a friend code, please PM me
I generally find the introduce a friend offer is a load of codswallop as they weedle out of it.