"..., right?" as a tag question
I always thought of saying "....., right?" as rather informal but one of my colleagues at the workplace uses it all the time when talking to our cutomers on the phone in English and she says things like "So you are planning to get there on May 4th and leave on May 7th, right?" and "You are flying economy class, right?" (We are a travel agency). I don't this way of talking is very appropriate in buisiness settings because it doesn't sound professional to me but she is convinced nothing is wrong with it. But then neither of us are native speakers of English.
Would you use "...., right?" when you are talking to customers on the phone? How about when you are a customer and talking to a travel agency? (eg. "The flight on the 23rd is booked full, right?")