I have two passport 9500 ix and one V1 .. the V1 has been sitting in a desk drawer for over a year. I think the passport does a better job of filtering out false alarms, and I love the red light camera and speed trap warnings.
The actual differences between the two units are small enough that you really can't go wrong with either one, imo.
I also prefer the ****** customer service. I had an issue with the second 9500 I bought. It had a defective case, and came unglued/welded at the seams. ****** dealt with the issue by sending me a new 9500 via fedex overnight and paying for return shipping for the bad one, and providing me a free three year gold membership kit for that 9500, and also the other one I already owned, which allows me 3 years of upgrades and updates to the camera/trap database, and it also came with a 12 volt power block so I could plug the detector in at my computer instead of having to haul the laptop out to the car.