I purchase all of my jewels at Tiffany's. My husband bought me my engagement ring at this branch. The staff at this branch, at least 11 years ago, seemed quite stuffy similar to the Tiffany staff at Mitsukoshi Nihombashi. I prefer to shop at the Tiffany's near Roppongi Hills b/c staff are much nicer. As for prices, no matter where you go: Vancouver, Los Angeles, Tokyo (as I have been), they are going to be comparable.
Most of the interior goods such as furniture, curtains, and large accessories such as mirrors require the customer to wait up until six months. This is because they do not keep enough stock at their warehouse.
Forget being able to communicate in anything but Japanese even though it is a British chain. Even if they say they are able to speak English, they cannot perform more than basic greetings.
IDC furniture store has much more to offer an more importantly, you do not have to wait 6 months to receive your items.