As mentioned previously, I am a radar/laser enthusiast. Before today I have never heard of the K40, but it seems like it is not effective. Check
this video out to see what I mean. In the video description it does actually mention that installs are typically $2500 so it is very likely that this is indeed the K40. Nobody will know for sure until you take a picture of the unit.
After a little research, the K40 seems like the same idea that Escort offers with the 9500ci. What I mean by this is that both are radar detectors with a combo of a laser jammer. The 9500ci and the K40 comes with a concealed radar detector and uses laser jammer heads to prevent a laser gun from acquiring your speed. It will also let you know when you are being targeted so you can slow down, and then turn off your jammer so that the cop doesn't become suspicious. These devices are illegal in some states much like how radar detectors are. There are also devices which claim to jam radar. For the most part (99%), these are false claims. A popular company which makes said claim is Rocky Mountain Radar. They are junk. Do not ever buy. In fact, even if they did work (which they most certainly do not) then it would be illegal to own since a device which interferes with a radar signal is illegal per FCC statutes.
High quality radar detectors are able to detect laser signals. The problems with these, however, is that if you are being targeted by laser, the a radar detector is essentially a ticket notifier since laser guns have the ability to clock your speed in about .3 seconds. Thus the best combo you can have for protection is a high quality radar detector such as: Valentine one (V1) and Escort 8500 series and up. Another thing to note is that Cobra radar detectors are junk. I shouldn't say all of them, however, because they recently came out with a decent one (XRS-9955 and XRS-9960g). Besides those two, I wouldn't ever rely on any cobra detector. In addition to a high quailty radar detector, it is also recommended that you get a high quality laser jammer. This will allow you to stop the officer from obtaining your speed and give you time to slow down (after the alarm goes off) so you can then shut down the jammer and he will get your speed. Under no circumstance should you ever leave it on all the time since this will most likely arouse suspicion and could possibly make them illegal (which they are currently not).
In conclusion, Cobras are junk (with exception of recently released model which is still a decent one), K40 is junk, and Rocky Mountain Radar is junk. If you have any of these it is better to sell them because if you get pulled over (which you will for relying on a crappy detector), the officer will see you have one and not be so lenient if he was to be otherwise. It is best to get stand alone radar detector and stand alone jammer for maximum protection.
Also, I have been wanting to get a jammer for quite a while but I don't have the appropriate funds. I was thinking of setting up a group buy in order to reduce cost of said jammers. If anyone is interested, please PM me and if there are enough people, then maybe we could all get a deal.
The jammer I would be interested is currently the best right now and is called the laser interceptor (LI).
Currently prices are:
$700 for 2 jammer heads
$1225 for 4 jammer heads
There are also High Powered versions (HP) which are mainly for larger vehicles. I doubt that a boxster would need this, but you can never have too much protection.
Prices for HP are:
$1400 for 2 jammer heads
$2450 for 4 heads
(cost is simply doubled)
They are pricey but it is extremely reliable and can jam all guns currently on the market. Take a look at
this site to see results of tests done by an independent group known as the Guys Of Lidar. You can also view radar detector results to see which one is the best. I currently own a Valentine one and I may be getting a concealed display to help hide the fact that I use it in case I get pulled over (also it allows you to move the display anywhere you want and still leave the radar detector in the maximum range location).