I was wondering yesterday if I should talk to Solent when I was passing just under the northern end of their Class-D by New Arlesford (D from 2500' to FL55), just to let them know that I knew where I was. I decided that it wasn't necessary as I was talking to Farnborough (and squawking a Farnborough code with mode-C), but if I was pottering about squawking 7000 would such a call be appreciated? Or am I better off just keeping quiet?