Of all the detectors you listed, I think the 795 is a good choice, no need to trade it in for something else. Although its performance is way below that of the high-end detectors, it will still offer you some level of protection, and is definitely better than nothing.
Honestly, I don't think there are necessarily "good ones" and "bad ones". Every radar encounter is different, and people might experience situations that lead them to question whether their detector is performing well. For example, if someone is headed toward the cop and the radar is aimed right at them, then they'll have very good range. But in some situations, people might experience a situation where the radar isn't aimed right at them, and it seems like the range is very poor, when in fact it is just the situation. |