Hi,
So I've seen everything from "Best Wishes" to "Best Regards" to "Sincerely" etc... I saw an email the other day that said "Respectfully" and then the senders name, is this ok to use? How would you interperet it? I would feel that the writer was trying to be very polite. I would also wonder if the writer was from a culture outside N. America, one where the concern for equality between people is less strong and the need for strong and overt statements of politeness is high.
Other than that, I wouldn't pay much attention to it. People do not usually spend ages analyzing every word in their email.
Best wishes, Clive