Bit late to the party with this one but my parents had an issue with Island vets, not sure of all the details but some medication was incorrectly labelled and caused an overdose, then when challenged for sending a bill for 'treatment' that resulted in the cat dying due to their incompetence Island Vets instigated legal action for non payment. Basically just bully's, they paid it in the end only because they had neither the time or inclination to go to court to defend the claim.
On another note Shire's are brilliant - we lost our lovely 14 year old collie last week and they couldn't have done more for him, first at the Stafford branch then at Stone for further tests, they were quick and efficient they made time for him and when it was apparent there was nothing to be done they let us be with him, well after hours so we could say good bye. I will forever be grateful for the lovely vet who looked after him. I cannot fault Shire, we've used them for years, they're not the cheapest but not everything is about money.