I like the Cargo version (RS-5) for two main reasons - the first is the comfort level, I can carry the camera with the F/2.8 70-200 mm attached pretty much all day without it getting uncomfortable and being able to just grab the camera and shoot and then let it slide back down to my side is fantastic. The second reason is the storage space in the RS-5, I can carry my micro fiber cloth, spare batteries, extra memory cards, pretty much everything I need and I don't need to have my camera bag with me at all. Best of all Black rapid actually makes an extension that would allow me to purchase a second RS-5 and link the two together should I ever decide I wanted to carry two cameras at once, which is pretty handy for the future when I do eventually upgrade my camera body.