I recently had the pleasure of dealing with Justin at Gem by Carati while shopping for an wedding band. Justin has a full set of crown sizing rings which was helpful for getting the correct size as they can vary slightly across manufacturer and the generic steel sizing rings other places have.
The buying process was extremely relaxed with no pressure and knowledgeable advice. Communication through various forms of communication was always great and everything went exactly as discussed. I never got the feeling that was discussed wouldn't be delivered and I am pretty a particular person with high expectations and Gem definitely exceeded them. Justin even went well beyond what I'd expect and is willing to help out my fiancée with an issue that is in no way his responsibility.
Honestly, I don't see myself shopping for jewellery anywhere else.