"I had a problem with a key for my Mercedes, they advertised a refurbishment service for £40 plus postage. seemed like a good deal.
I was very impressed with the fast service from the Master Locksmith - In a couple of days my key was returned to me with a new case, new batteries and looked great. They did what they said they would, promptly.
however it is important to realize that this won't fix all problems. In my case the key had become un-programmed, so I'm forty five quid worse off and no further forward. If I can get myself and the car down to London and pay another eighty they reckon they can fix it. or I can go to the garage and pay a bit more for a new key. With hindsight that would have been the best choice.
So they didn't solve my problem. Nevertheless their service was excellent. So although it didn't work out for me I'd not hesitate to give them a try."