Pete...search for this.. we recently had a great discussion on it.

The basics are..
If you see them.. and the detector goes off.. you are done.
If instant on is being used..it's not transmitting a signal for your detector to pick up until the signal to check your speed is shot at you.

Pretty much.. it'll tell you when to pull over. ;)

Yes and no Bill. As far as I have seen, all radar guns made within the last 8 to 10 years are instant on. Even the old ones had some instant on-ness to them. But in no way does that mean you are screwed. If in traffic, even a laser (the most precise as far as hitting one car and not setting off all the detectors in a mile radius) will give you warning. As Bill, said, there is scattering that occurs, and you can pick it up. Instant on radar, yeah, you will get warning, but it will be very on and off.

Bottom line: It all comes down to the cop. The good ones know how fast you are going before they tag you, it just confirms what they already know. With that said...they are waiting for you, instant on ready to go...

I disagree Logan...

If you are tagged with instant on and it hasn't been used previous to you being tagged. It's over. If the cop is randomly shooting everyone in front of you...yes..you might have warning. Most cops won't do this since it removes the element of surprise that their gun was designed to give.

Re: Radar Detectors
 

Drive the speed limit and you won't have to worry about it....

I prefer to fly by them. then look in the rear view mirror and say.
dont turn on the lights. dont turn on the lights. :D

If you really want protection from laser/lidar, invest in a good laser jammer.

http://www.lidatek.com/ they sponsor us we have 3 of there units totally undetectable full coverage. used for over a year with no problems got shot by the laser comming into Charlotte triple digits cop didnt even chase me.

even the passport and the solo 2 dont match up and they have great units.

Ha...ive done that a couple of times....Once I see the squad, I know they have seen me. I don't even slow down... I got pulled over once in my life. I was 18...I am now 42.
I drive 5 to 10 miles over on the freeway, depending on my confidence level. I go 5 over on most side roads. Nothing over in residential areas. That's what I feel safe at.. works for me

I have never been pulled over while having a radar detector in my car. (not for speeding anyway). As of right now I have a Cobra 12 band detector that I got for Christmas and it saved my butt yesterday.

Those of us who have been using them for years (me since the 80's) have developed good habits and skills. We have proven time and time again that you can make detectors work against instant-on radar or laser if you drive smart and aware.