I bought a XRX a few months ago and finally had a chance last weekend to take it for a cross country flight. On my way back home, my second to last waypoint, was over a smaller uncontrolled airfield. I was in a low wing plane, cruising at 3000 inside and talking to the TMA controller.
A mile or two before crossing over the small airfield, my PCAS made a small blip and displayed traffic 12 o'clock and -2500 below. The traffic was right below my nose, probably just took off from the field. There was no way for me to see it with my eyes because it was below me but the Zaon was telling it was there. It then showed it climbing up to 1300 feet or -1700 relative to my altitude but parallel to my direction. It was persistently right below me.
We continued forward and about 5 miles further the TMA controller told me to descend to 2000 and that there was VFR traffic below me, a mile to my right at 2 o'clock. I tried looking but just couldnt spot the bugger, the PCAS was showing it but my eyes were not picking it up. This got me nervous so I did a 45 degree bank to the left and made ample room between the two of us. After this I was able to spot him below my right wing, it was a high wing Cessna. He was flying in uncontrolled airspace, below me to my right, and probably completely oblivious to my presence above him.
We were able to keep visual separation all the way home but it got me thinking. If I hadnt had the PCAS, I would not have known of him until the controller told me about it. The controller did not say the direction of flight for my traffic, so I wouldnt had a clue if the traffic was still there a few moments later. The controller told me to descend, practically straight towards the traffic. Again, I was in a low wing, the other guy was in a high wing. At that moment, I was happy to have the PCAS, I knew it was paying back the investment in a very meaningful way. The Zaon does not relieve you from doing a proper scan, but in situations like these, its a priceless tool.