I have tried several different designs and types of small bag that are idea for a day out, basically those that are designed for a single camera body with a lens attached and maybe another one of two lenses, or a bite to eat!
I have been very impressed with the Kata H-16 for several reasons. It will comfortably hold either my 7D or 30D with 100-400mm lens attached with a 100mm macro lens in one side pocket and an 18-55mm lens plus some food in the other side pocket. In the top part of the bag you can fit several memory cards and a spare battery. With all the padding on the inside of the bag and the tough outer material I feel comfortable that any knock that my bag may take would not impact on my equipment. The strap is very comfortable, it doesn’t rub at all and does not slip or move around when hiking, climbing or moving around. I have scrabbled over rocks and rugged coastline and the bag did indeed take a couple of knocks, but I am happy to report that my equipment was perfectly fine, maybe I can get some of this tough, protective material for my legs!!
The dual purpose elements cover fits very quickly and easily on to the bag and the design still allows quick access to the bag if you need it just by loosening the pull cord you can flip the cover off from the bottom of the bag. As of yet I have only used the rain cover, but I have used this on boats where there has been a lot of salt water spray and out in heavy rain and it has kept the bag completely dry. The cover itself is very easy to clean and dries quickly. As soon as I get the opportunity to use the heat shield I will post an update!