I upgraded from the Passport 8500 to the 9500ix. The 9500ix is worth it's weight in gold. First, any of the Passports will pay for themselves in a month or two if you drive fast in a highly patrolled area. Second, the 9500ix never ceases to amaze me. The GPS for the redlight feature is nice downtown just to give me the "hey *******, redlight camera coming" reminder. But what makes it worth the price premium is the GPS integration for learning false alerts. Living in downtown Chicago, I have numerous businesses in my area that used to set off my 8500. When I got the 9500ix, I just drove around the neighborhood a few times and the darn thing learned every single false alert. Now it's dead silent unless there is a cop or a redlight camera approaching.
Hands down one of my best purchases of 2009...and my wife will tell you I buy things constantly