I've got an AutoX-Ray also, with the pc link (got the pro pack), and it's been great. Nissan vehicles won't give me as much data as Ford/Gm (I added the enhanced data options for those also), but it's still useable.
I got the Xray for a lot of different vehicles, not just Nissan, and I needed to read older ADL and ford codes aswell as new OBDII, so the Xray made sense.
It's constantly being updated too... Xray does a good job of keeping it up to date.
If you are just working on the one nissan truck, however, I'd buy something cheaper. I needed portability and convenience, and a wide range of compatibility.
-=RB
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