I have several devices that are prone to getting dusty, including BaoFeng, QuanSheng, Weinone, Lianchang, Hytera, and Desheng, as well as old cell phones and tablets. When I want to use my walkie-talkies, I check the battery levels of all the devices, and I always find that the QuanSheng K5 and K6 are the ones with the lowest charge.
Therefore, if the walkie-talkies are intended for emergency use at home, it would be best not to use the K5K6 model.