Which is the best affordable radar detector?

I am looking at getting a new radar detector for my car. I currently have a freebie that my friend gave me. It's the Cobra XRS7330. I don't want to spend a ton of money to get something like the K-40. I was looking more around the Valentine One, The Cobra Xrs R7, and the Pport 8500 X50. Does anyone know of any good reliable and mildy affordable radar detectors? It does not have to have GPS because they don't really use that in M.