I had a V1 years ago and swore by it as a means to keep my record clean and then stopped to think about the "why" and gave it up.
Once upon a time I took an attitude that almost any reasonable law enforcement individual would give me 9mph over the posted speed limit and not lift a finger. It worked for many years with no driving record infractions whatever. I started buying cars that made exceeding those parameters far too easy starting with a 2001 Audi S4 and you might be guessing the outcome already - my driving record was (ahem) less clean than before. I bought the V1 to make my life easier.
In my area there are still lots of local county sheriffs squad cars with olde fashioned X band radar that is on all the time while they drive around. That means you HAVE to leave the V1 set to it's most sensitive mode in order for it to be useful and therein lies the rub. That sucker will trip on almost every retail store door opener in town and you will live with the almost constant din of the system going into alarm mode while you are driving.
I finally came to the conclusion that driving with this in my car was actually less gratifying because I always had to take the attitude that if I heard anything at all, I had to slow down immediately or possibly face another ticket. I noted that it was a knee jerk affair with the radar detector alarm - the second you heard it you must react and that included all of the occasions when you were driving even at speeds that required no reaction at all.
I got tired of driving with a hair trigger on my dash and sold off the V1. I now enjoy driving far more than I ever did with that device on my dashboard and wouldn't even consider buying one again.
Do bear in mind that police officers view the very presence of this device on your windshield as evidence that you have INTENT to break the speed laws and as a result will not even consider a warning if they have pulled you over. They are looking for the suction cup marks on your windshield in case you yanked it off while pulling over and they did note it if they saw it before they turned on their lights. You may not like this line of thinking but there are law enforcement internet forums that are discussing this very topic and there are lots of participants that intend to enforce the exact letter of the law if they see you have the detector (or evidence of it) in your car.
I am back to my 9mph over the posted speed limit personal boundary and am now well over 3 years without a ticket and enjoying my drives a lot more without the screaming alarms from my dashboard.
BTW - I do typically get TONS of high speed driving time at my local track where no one cares the speeds I drive unless I am holding them up
