I do both on the Arrow I fly.
Some will argue that leaving the gear down longer just freezed the slush
faster. To me the most important is to blow it out of the brakes.

Paul Tomblin wrote:
This will be my first winter flying the club's Lance. One instructor told
me that you want to tap the brakes before retracting the gear to dislodge
any slush or snow so that it doesn't freeze in the wheel well, and I read
somebody else saying that you should hold off retracting the gear after
take-off for a little while to blow the slush and snow off. Should I do
one or the other or both?