I'm so sick of my P7 light. I've tightened up the assemblies, adding paper spacers to my batteries, and snugged up the cap with magnets: nothing can make these POS flashlights reliable. Mine can barely make it a few miles without flickering or changing modes. It started flaking out with in a few months of getting it.
Planet Bike lights are expensive in terms of lumens/dollars, but they are rock solid investments. I've got two superflashes and a 1W blaze for "be seen" lights, and they've been going steady now for over two years through thunderstorms and -40 winters.