I am in violent agreement with you!
I used to have a routine when I got in the car, took me about 5 minutes plugging in all the toys [GPS based camera detector, Radar/Laser detector, sat nav, trafficmaster] would be late leaving as a result and needed all the speed tools to get me where I needed to be on time!
So I have combined 3 of those, GPS speed camera detector, Satnav and Traffic information in one and dropped the radar/laser detector, have to say if I could find a unit that did all 4 and only gave radar/laser warnings where it hadnt already warned me as a result of GPS position and then only when I was over the speed limit I would probably buy it.
Going back to the original posters question I'd still spend my money on a gps based satnav unit and download the speedcam database from pocketgpsworld.
no matter what detector you go with it wont protect you from the unmarked car, truvello cameras (the forward facing ones), SPECS (the average speed cameras they increasingly use on roadworks) or whatever they think of next in their flawed thinking about speed (http://www.safespeed.org.uk/ RIP Paul Smith ) only a GPS unit will protect from them all (with the exception of the unmarked car!)
+1
And can back the Origin speed trap detectors, great product.