Review on humangear capCAP+: The Ultimate Blue Bottle Cap for All Your Hydration Needs by Justin Ferguson

I think this is a definite improvement over the original cover. The jury is still out for me as I've only had a few weeks but otherwise no major problems. There is no problem with the gasket itself, but you need to check when you unscrew the small plug, especially if it has been screwed very tight. If it is, the large seal can come loose when you open it, and you might not notice until your stuff gets wet. I just open it with both hands, holding one hand most of the time.