Yeah my 4 Silver is going to be replaced on warranty. As for the Silver vs. Session, apparently the battery life is a little better on hte Session but it won't record for very long if you just leave it going -- 2 hours or so, from one review I read, so it's better if you just have it record short things and you remember to switch it off when the road turns into a straight line again. The Silver won't last that long of course, so it depends on what you're doing. I like being able to switch the battery out at a stop, so if you have a couple of those, you can be a little more lazy with the Silver (also provided you have a big enough SD card). I tend to switch off the back screen once the mount is set up and everything, because you can still control it perfectly well from the little front display.