I guess that would be appropriate for the "present generation"!! FWIW - I guess this is "historical perspective only" - in the olden days (I soloed in 1969 and got my Private Pilot License in 1970), the standard gift was a bottle of the CFI's favorite adult beverage - no cheap stuff, something good - given after the successful completion of the checkride for the certificate or rating. In my experience, as both a student and later as a CFI in the early 1970's, gifts after solo were generally not given back then.