It really comes down to what your budget is and what features you want.
Mine is parked securely so I didn't see the need for a £100+ one that has parking mode and all of that stuff, so I'm pretty happy with this which is frequently discounted down to about £30, the image quality is good even at night time and you can get files off it using wifi if you don't want to pull out the SD card.
You'll pay a lot more for parking mode and particularly subtle cameras, it does the job for me. The cabling etc, isn't to do with the cam itself, it's more down to your car when it comes to how easy it is to get wires behind the trim and into the fusebox.