My favorite mode on the Passport 8500 is ExpertMode, which not only tells you how many bogeys you have, but what bands they are and their relative signal strength.
Since you can use signal strength to denote position, I consider the V1 to be less informative (I have driven with one). In the various caravans I have been a part of, I have never been in a case where the V1 was alerting prior to my 8500, allowing for location in caravan.
