I bought the Sling because I found a backpack too heavy for my back (I have back issues). The Sling was great choice and I added a Capture to carry my camera on the outside. This gives me plenty of room for lenses and accessories. Such a quality product at a very reasonable price.
I have used this for a year and it is good. I had the 10L sling and it fit most essentials in it. I could fit a 11" surface go in it so I could carry it in for class too. I like the adjustable strip so I can switch to run and gun mode very quickly.
But non retangular size mean also you can't fit a lot when you really have to. If this bag has some kind of flexible feature to expand could be really good.
I got the 3L to use as a daily carry for small items, including my Fujifilm X-T2 with 28mm pancake lens (or sometimes the 35mm F2). I was looking for something compact...and this was definitely that...but in the end, after adding more stuff to it that I normally carry around daily (wallet, metal straws, reusable grocery bag, wipes, hand sanitizer, small battery pack, sunglasses/reading glasses, etc.) I realized it was a bit too small for my needs, so I ended up selling it to get the 15L Zip.
Having said that, I really liked the bag for its solid build quality and materials. In hindsight, the 6L probably wouldn't been better for my needs because I always want to carry a camera around...but then again if I started to stuff that with some weight, I wouldn't have liked it all on one shoulder anyway so that's why I went with the 15L Zip in the end.
A great bag for holding a mirror less camera and an average size lens. The woman in the promotional video is some kind of Marie Kondo wizard for fitting so much in it. I have no such skills. But I still like the bag.
This is my third peak design bag. I love my other two so much, that it was a no brainer to order this when I needed something smaller for day trips with my new (smaller) mirrorless camera. I also wanted something smaller that would still hold my camera and a 70-200mm lens. The everyday sling is now my go-to when I want to bring a camera and one or two lenses on short trips.
Pros: * Fits my a7rIII with a lens and I can pack an additional lens as well. * Bag is very solid and not flimsy at all(this is actually a blessing and a curse) * Built materials seem to be very good.
Cons: * The stiffness of the bag makes it difficult to add more things in the bag. Yes I can buy a bigger bag but I like the size of this. Perhaps a 4L would have been better if they made one. * Strap connector - I don't like their weird connector that they use to disconnect the strap. The metal clip they use is very thin and I don't see how it is much better than the traditional plastic connectors. It takes much longer to detatch. * Extensions - The hooks on the extensions do not stay on unless you tie down an item. This could have been implemented better. * Front pocket - It is very difficult to get things out of the front pocket because of the stiffness of the bag. Adding some sort of flex material for the front pocket would have been a better idea.
Overall, this bag would be perfect if it wasn't as stiff and if it was ever so slightly bigger. If I didn't get this as a gift I would have returned it ASAP.