Switched power feed

Hi guys,
I’ve got a 2002 V40 and I want to connect my speed camera and sat nav to a switched supply. They are on the bottom right of the windscreen (if sat in the car) and I was going to use the cigar lighter socket, but that’s permanently live, so where would be best to tap into, the HU?
Cheers

Probably better taking a feed from the battery, with a relay signal from the ignition.

Good idea, thanks.