If you want to know how radar detectors/laser jammers work, I believe a member made a thread about this before and it was a good read.
I have had quite a few radar detectors and here are my takes on them.
~Any cobra - I honestly would not get any of their shit
~Passport Escort 8500 x50 - pretty basic and simple, but comes with very few options. But it's compatible with the ZR3 laser jammers so that combination would be ideal.
~Valentine V1 - I actually had it for 2 weeks equipped with euro mode and POP2 and everything... and then sold it because it really wasn't all that to me. The arrows and bogey counts were cool and all but in the end, I really liked the 8500 x50 better because it actually tells you the type of radar on the big LED. On the V1, it tells you but via little dots and it doesn't tell you when you're being hit by a laser like any passports. The only neat thing is you can send it back to Valentine and they'd update it for you. the fucked up thing is you got to pay for the update.. IMO I'd rather see an LED while driving rather than having to dicipher a certain series of beeps like morse codes that comes from an obsolete looking block =P
~Passport Escort 9500i - I upgraded to this from the V1, and it's pretty much just the 8500 x50 with the GPS system. The cool thing is IT FUCKING TALKS like a navigation system, blocks out false signals once it's been through it before so you don't get false alarms the second time around, it tells you your speed limit everytime it receives a rdar signal. Moreover, you can choose to mark certain locations for speed traps if you KNOW cops are bound to be around there and it'll remind you (i.e. 285 near peachtree industrial).
So yea, it may seem like I'm bias towards Passport but I just tell it how I see it. The thing about this technology is that they come out with new shit everyday and you have to contemplate depreciation value. Like when I got the x50, it was 350. I just sold one earlier this week for 160 -___-'. It seems like only the V1 and 9500i/x retains their value..
That said.. hit me up if you want a 9500i.. $350