go with a 9500, cheaping out on radar detectors is just a waste of hundreds of dollars, even from the 8500 to the 9500 i noticed a huge improvement.
if you want a jammer, i think they sell a jammer/9500 kit together. its over 1000 bucks. radar jammers dont work, laser jammers do, and pretty effectively. so if your safe from laser, and can detect radar, your pretty damn safe. and you can rig them up so the jammers are very well hidden, and have an on off switch, so right after you slow down to speed you can turn the jammer off, then they get a reading of you going the speed limit instead of staying on an error reading, then it doesnt look like you have a jammer. they are illegal in quite a few states, but you dont get in much trouble if you have one, a confiscation maybe a small fine if anything.