Just fitted an RCD 330 plus. It’s very good.
I have an ‘08 plate and Canbus was fine, no battery drain. Also, aerial adapter did very little to improve reception. With just the standard white aerial lead connected while I waited for the adapter to arrive, it was just fine. That said for £8 I’d still do it just to be neat and tidy- however the aerial leads only go one way around and aren’t marked or colour coded. So if after connecting up you have poor reception, (esp. on AM for me), swap them over!