There are two really good radar detectors out there: the Valentine One (and higher up models of it) and the best model Passport Escort. Other than those (which are very expensive), you have to realize you are getting what you pay for.
I got my Cobra knowing it wasn't the best radar detector out there, but it has served its purpose well. It more or less serves as a reminder for me to watch my speed, but it has definitely paid for itself in that it has warned me of speed traps and police on a few occasions when I wouldn't have seen them otherwise or didn't realize how fast I was going.
The laser detection is mostly useless because by the time it detects it you've probably already been tagged, unless a car in front of or behind you has been tagged instead. Recently it has been doing its job very well, picking up almost every Ka band within distance as well as K bands. Granted, I will occasionally pass a cruiser that I know has its radar on (blatant speed trap) and it hasn't gone off, but most of the time it does. It is important to remember that it is not a "police car detector" but a radar detector, and it will only sound if the cruiser is running radar at the time. It picks up frequent X bands which these days are usually waves from automatic doors and supermarkets. The false alarms are kind of annoying, but the sound for X bands (usually the only false alarms) normally lasts only a moment before you pass the area. In the event it goes off for an extended period of time, the controls are very simple and allow you to silence it immediately.
There are highway and city modes, but highway is essentially useless because it merely alerts you of X bands more quickly and as I said, these are normally false alarms. Also has some intelligence features that I don't use, and three light strength options. Good detector for the money if you know what to expect, and better than nothing.