Certainly in the UK there's not much point scanning anything other than Radio 1 (or another BBC national station). It sends notifies for all regional TA transmitting stations. Perhaps a programmed TA station would do the job (I believe that's what my Blaupunkt head unit has).

This only applies when you're in player mode anyway - in tuner mode I don't believe it is possible to retune for long enough to acquire RDS without hearing an audio glitch. At least, not without two tuners (which some head units have).

Rob