This is not a paid endorsement and I’m not affiliated with BlackRapid.
The reason I use the BlackRapid Curve (RS-7) camera strap is simple, it’s more comfortable for my back. In case you aren’t aware, the Curve (RS-7) is a sling-style camera strap. The RS-7 is worn just as you would wear a messenger bag, slung over one shoulder and across your upper torso. The camera hangs upside down (attached to the tripod mount) at hip level.
I found with a regular neck strap, my neck, shoulders and upper back would ache after a couple of hours. While I cannot claim pain-free multi-hour photography sessions now that I’m using the RS-7, it has nonetheless helped tremendously to reduce the strain on my neck and especially my upper back. You might be surprised how much lighter your camera feels hanging from this strap compared to a neck strap, and it has the added benefit of keeping the camera at your side (even slightly behind you), which keeps it out-of-the-way during times when that is desirable. And I always found it irritating how the camera would bounce and bob while walking when using a neck strap. With the camera hanging at my side, it generally stays in place, at most rocking back and forth, but not bouncing. And when the time comes to take the shot, I find it no less convenient to grab the camera from my side. Maybe it takes a fraction of a second longer than lifting it from a neck strap, but if I find myself in a hectic and fast-paced situation where I need to get a shot, I probably should already have the camera in my hands. For my purposes, any sling-style strap probably would have worked, I chose the RS-7 because it appeared to meet my needs at a price I could accept (just over $60).
I’ve owned the RS-7 for a few years now, but only recently started accessorizing, adding the BlackRapid “Brad” accessory (can be seen attached to the RS-7 in the picture above) which is an underarm stabilizing strap. This accessory is designed to prevent the RS-7 (and other BlackRapid straps) from sliding up and down. While I didn’t have much of a problem with this, from time to time the RS-7 would slide up and down and I would need to adjust it. I haven’t used it in the field yet, but the Brad accessory looks like it will completely eliminate that “problem.”
I also added the “Joey 3” storage pouch accessory that attaches to the lower front part of the shoulder pad section of the strap. This puts the storage pouch at chest level and is good for storing extra batteries, memory cards, a smart phone (although it may not be large enough for some phones), and even a small point and shoot camera. I plan to use it to hold my Sony RX100 II compact camera. This will be a great way to have a second camera offering focal length flexibility on photography outings where I only take my Nikon D7100 with a prime lens like my 35mm or 24mm. If you want built-in storage in your camera strap without the need for an additional accessory, for $10 more than the RS-7 you can get the BlackRapid Cargo (RS-5) strap. But for my purposes, I think the RS-7 paired with the Joey 3 is a better option because it offers enough storage capacity for a small point and shoot camera, something that does not appear to be possible with the RS-5 (without accessorizing).
And last, I added the BlackRapid Tether Kit, giving me some peace of mind that my expensive camera and lens won’t end up falling to the ground. Don’t get me wrong, there’s nothing wrong with the design of the RS-7 and how it attaches to the tripod mount, I’m simply paranoid. If you too are paranoid, and you decide to purchase the RS-7, you might want to consider the Tether Kit, which uses one of the neck strap posts as a second connection point back to the main strap. It will save your camera in the unlikely event the tripod connection comes loose. If you don’t like the cost of the Tether Kit ($23), I can offer you a cheaper alternative, just buy the OP/TECH USA System Connector Uni-Loop ($7), connect one end to the neck strap post (opposite the grip), connect the other one to the metal rectangle that slides up and down the RS-7 main strap (don’t connect to the loop that is part of the tripod mount because that will partially defeat the purpose of connection point redundancy). Then connect both ends together. Now you have a cheaper alternative (which I have personally used) to the BlackRapid Tether Kit.
With the BlackRapid Curve (RS-7) camera strap I’m able to relieve the strain on my back, while still lugging around my Nikon D7100 and fairly heavy Nikkor 24mm f/1.4 lens, and I have the added flexibility of bringing along a high quality compact camera and storing it in the Joey storage pouch. What this means is on most photography outings, I can leave my bulky camera bag at home, which also helps the ailing back! And that was precisely why I bought the BlackRapid Curve (RS-7).