There's a lot of bad information floating around about this topic. I'll try and clear some of it up.
The laser interceptor works. It's the only system that will properly defend you from a LIDAR (laser) gun. Laser is not like radar. It is specifically targeted at each specific vehicle and typical tracking distances are less than 1500 feet although they can exceed 4000 feet with a steady hand. Usually topography keeps the distance much shorter. Unlike a radar wave that expands out from the gun and is about 150' wide at 1500' a LIDAR beam is about 10' wide at the same distance. This drastically reduces the chance of any LIDAR detector picking it up before you are tracked and nailed. Cops (at least the ones who know how to use this equipment properly) don't just shoot vehicles indiscriminately. They'll visually track the fastest car in a group and shoot that one. Or if you're alone and shot directly you're toast. A LIDAR beam travels at the speed of light, out and back. When your detector goes off with a laser warning it's only telling you to just pull over and get your ticket.
In short, with LIDAR unless you have a jammer, and AFAIK the Laser Interceptor is the only one that works, you are totally at the mercy of the men in blue. I see where delma411 had a Rocky Mountain Radar product. I hate to tell you this man but your success was one of luck, not good equipment. That stuff is junk and has never been shown in any test I've ever seen to actually work.
With radar a good detector gives some serious advantages. There are a lot of lazy cops out there who leave it active all the time rather than properly targeting and transmitting in "instant-on" mode. If you are going to get a RD then I'd only look at products from Bel, Escort/Passport and Valentine 1. They are the best out there and the performance envelopes are so vastly superior to the competition it's not even funny.
Even with a good RD you need to drive/ride smart. Use a rabbit if at all possible. There's always someone in a bigger hurry than you so let them go by and trail them 1/4 mile or so back. If there's an instant-on trap ahead they'll be the one getting a fast driving award, not you. You also need to know your detector. The good ones can get a signal at 2+ miles and it may just be a very brief chirp. Take every warning seriously. Ignore them at your own peril.
I'd also recommend using other traffic to screen yourself as much as you can and stay out of the fast lane on the interstate.
I have had a Passport 8500 X50 since 2005 and have been more than satisfied with it. The new 9500i is supposed to be even better. I've had Escort products since the original Escort I got in 1984. Solid stuff, then and now.
I took my 8500 with me on my cross country ride but it was impossible to hear and almost impossible to see in the daylight so I abandoned it to my bag after I got to South Dakota. The speed limits out there are high enough where I could ride around 75-80 and just not worry about it. In most cases if you are going 9 mph or less over the limit you're not worth the time to stop and ticket. Way too many better targets of opportunity out there. There will always be exceptions to that rule but in the South, Midwest and West it seems to follow though. You folks above the Mason-Dixon line...I dunno. I can't ever figure out what y'all are doing up there anyway.
If anyone has any specific questions please post them and I'll do my best to answer them. I spent 5 years in a traffic unit and am a certified radar and LIDAR police instructor. I got to know the Kustom radar people very well and can tell you just about anything about their equipment. You might also check out:
This cat is an ex-LEO and he gives totally unbiased, objective reviews on the speed detection products out there.