I have used an X50 for almost a year and now I have a V1 to test drive. Most people on this board have only tried one of these detectors, so I thought I'd give my opinion on the subject since I've tried out both of them.
When I had my X50 I was sick and tired of the POP falses. The detection range was outstanding(saved me more then a handful of times) and the unit didn't false that much. I must admitt I bashed the V1 a little bit because I used a 3.824 in the past and it falsed much more then the X50.
I bought a 3.825 brand new from VR and I must say it's my favorite radar detector now. This rev. number falses almost LESS then the X50. I don't have to turn the POP off like the X50 and the arrows are really cool.
I think VR fixed the K band falsing problem and I haven't had one KA false yet. My detector is in advanced logic mode with X band turned off.