I had a

If you shop around you can get a guarantee of up to 5 years . Depends where and how they are made .

Your dentist is right that this crown is structurally sound but if you do not like the appearance then you should go back and discuss it with him
It would be impossible for it to wear in a few days meaning that it was either made with thin porcelain or adjusted to allow space for the opposing tooth.
It all depends on the "small print" of your contract with him as to whether he promised there would be no metal show through on the crown but most dentists I know would prefer to replace a crown that a patient disliked as rather that have adverse publicity

The crown was proud in the bite and therefore your dentist needed to adjust both the crown it self but also the opposing tooth. Small amounts of adjustments are perfectly acceptable. It is very difficult to make a crown, especially when the bite is not perfect that requires no adjustment at all.However these should be small adjustments and should ideally be re-fired with new glace over the adjustments as the glace will have been removed during adjustment. When using ceramic fused to a metal substructure type crowns, more tooth has to be removed to allow sufficient space AND THICKNESS to prevent fracture from happening. I think it sounds like the ceramic on the crown was 'thin' or insufficient space was allowed to accommodate the crown, hence all the adjustments. Since the metal coping is intact the tooth is actually fully protected underneath. However there is a growing emphasis on cosmetics and I would expect for that price that both function and aesthetics were delivered on. I am sure that your dentist will agree to re-visit the crown if you have this conversation.