I use Caras regularly and always have been happy with them.
They did some custom pieces for me which came put amazingly well. The key is that I gave them the time to do them and they were calling me regularly to come and check all the steps of the process to ensure it was as I wanted it. It came out better then expected, every time.
Went with my MIL today to Caras, between us we had 6 items to be 'dipped' and 20 items of yellow gold to be cleaned. I was told it would take an hour so came back 2 hours later to make sure they were ready. However, they weren't, the salesman spoke to the manager who unfortunately did get annoyed at the salesman. Upshot was that the manager apologised and asked for my address saying he would deliver them to me. And within 2 hours he was true to his word, my items were delivered,lovely and shiny, and no charge to my home (Jebel Ali). What service.my MIL is on holiday from Scotland and is very impressed with this service. Well done Caras.