@Cederholm , I bought the Defender 2 display package with wireless wind sensor late last season and haven't installed it yet. I was very interested to see how
@Tin Kicker installed it. I was somewhat planning on installing the blue tooth sensor next to the external GPS near the back end of the boat for a clear signal. I may have to reconsider and possibly mount it closer to center of boat and possibly interior. That gives me something to ponder before I complete installation! With some hesitation, I did finally decide on the wireless because I, too, do not want to pull the mast, even though I already have a wind ducer at top (I'm not sure the cable would be compatible or it may have a discontinuity that has been causing problems with my current RM i60 wind display). Also, I noted that Sailing Uma has been using a wireless B&G wind sensor, which has worked flawlessy during a couple-years service including their time spent above the Arctic Circle! They only needed to change their battery when it's time was up. So, I figured it was worth a try.
I think this system will work very well with the Vulcan CP. I had the wired B&G system with a Vulcan 7" CP on my Starwind and the external GPS was a necessary component for the sailing features, plus it added tide information that could be displayed on the CP. I know few of the technical details, but I would say that the external GPS adds far more than simple redundancy to the CP-loaded GPS.
That said, I also purchased a 12" Zeus CP last fall and used it quite happily on its own for awhile. The price for left-over models was ridiculously low. I had a pod that mounted my (previous-owner supplied) Garmin CP and the autopilot control on the angled shelf of the pedestal guard and a separate pod for the 3 RM displays (depth, speed, wind). I've decided to get a new pedestal guard and I'm only going to mount the single pod on the angled shelf. The pod that I purchased with the Zeus is pre-formed to mount the 12" Zeus and 2 displays. I'm going to mount one of my B&G Triton displays on the pod and the wheel pilot control (RM ST6002) for now. If I want to mount more displays, I'll deal with that later on a separate pod. I'm going to mount the 2nd Triton instrument display down below, which is where I've always wanted to have a display at the nav desk. I've got 2 thru-holes for ducers (speed and depth independently and I'm going to have to enlarge one hole for the DST 810. I will probably use the other hole for the existing depth ducer as back-up but I haven't decided where to mount the display.
I think Defender puts together the best packages, and I will always opt for buying those packages as opposed to buying components separately. I believe the package includes a N2K starter package, but you may have to purchase additional networking components depending on the complexity that you need with the displays, CP and tiller steering components you may buy. With respect to all the commentary on sailing with limited instrumentation, of course most of this stuff could be completely unnecessary. But, I like to have it and it's MBMC!