Do I understand correctly that ADS-B traffic information comes via a ground station somewhere?    How does that actually perform when you are in a valley somewhere?

I used to have TIS-B.  I loved it when and where it worked but there were enough discrepancies + the fact that you had to have line of sight to the Radar facility that I was really enthusiastic about getting my ryan 9900BX.   The very best thing about TIS-B is that it showed me how much traffic I wasn't seeing.   However, the delay and coverage issues are real.    One incident I had, I was at the range limit of the Sacramento facility when I saw a blip at less than two miles 10 O'clock.   I looked up and there was a mooney headed straight at me.  I dove to the right and no sooner than he had passed my tail, he disappeared off the screen.   If I had been a mile further south I never would have seen him.   Another incident: as I was going into Palo Alto I had several targets coming up at me.  One was 12 O'clock and reported as 300' below me and climbing.   I was about to climb when I spotted it already above me.  That is where the delay was really a problem.

Dico,

IMO in a IVP you will be very happy to have an active system like the avidyne TAS 600 or 605.   The former is only $8490 and you can install it yourself.   The latter list is a little over $10,000.  (You can probably find it cheaper....or you can find someone who is gaga over ADS-B and make them an offer....)   You'll find it works much more reliably,  regardless of geography and doesn't have the delay of going through a ground station.

The 600 gives you coverage up to 18,500 above which you have radar separation because you will be IFR.

Colyn