Has anyone ever gotten anything engraved at Tiffany's?

We got 2 TIffany champane flutes for an e-present and I wanted to have them engraved and use them for the wedding. I figured I would be better off getting it done there since if they mess them up, they can replace them.

Does anyone know if it is expensive? The glasses are about $35/$40 each so could engraving just our first names and wedding date really cost a fortune? (as most things do there!)

(I called but they can't estimate pricing-they have to sit down with you!)

TIA!