I'm sure you will get a variety of opinions so here is mine. I use MF and LF so weight is a concern but after trying different types of bags and straps I settled on a camera backpack. I suggest getting one that is larger than you think you need since it can also hold rain gear or other stuff. The nice thing about the backpack is that it is easy to carry more weight and both hands are free. if you bend or twist you don't have to worry about a strap sliding off your shoulder. You do have to remove it to get things out though. My photography usually involves having the camera on a tripod so that is no big deal. They usually have adjustable padded compartments so it can be configured as desired. A good one has sturdy, water resistant or waterproof material and high quality zippers. The one I have is from Tamrac and has been in use for seventeen years and remains in excellent condition while having been in rain, dust, heat and cold, in and out of car trunks and overhead airplane bins.