I just got the white's v-3 and really like it so far. I think I'll like it even more as time goes on and I learn more about the detector.
I have owned 3 detectors, all whites so I can't comment on the others. I started with a whites and have never found a reason to switch.
My experiences have been great customer service. My white's dealer always goes above and beyond in that department. What ever machine you choose Isn't as important as learning that detector and having confidence in your choice...good luck and happy hunting