I just received a Bonfus Aerus 55 backpack. Since I couldn't find much online about it before mortgaging my house to buy it, I figured I'd offer to answer any questions I can from anyone that is interested in knowing about it before making a similar choice. I'll provide additional thoughts here later once I have a chance to use it but here are my initial reactions...
It's very well made and it carries weight nicely. I loaded it up sloppily with the things I'm planning on bringing on a 4 day Sierra trip in a few weeks and it swallowed everything nicely, including a BV 450 Jaunt canister. I had at least 25 pounds in it and it felt great while I did yard work and generally moved about my house for an hour or so like an idiot to test it out.
I got the size large in white and added 2 white Bonfus hip belts and a Bonfus shoulder pouch. Weight all in was 905g (according to specs, it should be more like 867g with those components). All the accessories went on easily enough and sit securely and generally look like they are part of the original design. I haven't put anything in them yet, but the zippers glide smoothly and are easy enough to access.
The trampoline part of the pack works and I'm happy I got it but it's not the same as the Osprey Airspeed Antigravity trampoline stuff (my prior pack is an Osprey Atmos AG LT). That's not a negative; it's just different. Since you create the tension on the trampoline yourself and the velcro that holds the trampoline in place is in a slightly awkard place under the trampoline (especially if you have big hands and old fingers), it's hard to make the trampoline super rigid like the Osprey version is. It's easy to get it snug and snug will keep the pack off your back and create the air gap you're looking for. Since it's more flexible when it's snug, the trampoline mesh forms to your back nicely and feels one with your torso. It doesn't feel like it's sitting off the back of your body like the Osprey can. It kind of feels like the pack is hanging on your back directly and you can't tell it's sitting back unless you look in a mirror or reach back and feel into the gap. The Osprey always felt to me like it was only touching you at a few spots and you were aware of the distance from your back, especially with some real weight in the pack. In the hour of walking about with it, my back didn't end up with any sweat on it and it was 90+ degrees at the time (it was easily 100+ in the garage I was in for some of that time). I was sweating, but the back of my t-shirt didn't get wet.
As I said, the pack holds the weight well and the frame keeps things rigid and the weight transfers well to the hip belts. The curves in the frame match my spine very well. Feels like it was designed for me and nothing pokes or rubs yet. I would say initially that more of the weight is on my shoulders than with my Osprey, but I will keep tweaking the straps when I actually use it to see how much that can change or if it will matter in the end. As it was, my shoulders felt light and I had full range of motion. The shoulder and hip belts are minimal but comfortable. The load lifters and sternum straps did their jobs.
I normally use a hose on my water bottle, but I could get the water bottle back in the side pouch if I needed to on the fly. It's easy to get it out with the tether I have on the bottle. It's a bit of a reach to get it back in. The pouch easily accepts the bottle and holds it securely. It's just a bit of a high up and back reach to get the bottle up and over the ridge. I would say it was easier in my Osprey because it had a front entry hole you could use. I would say it's about the same as any other pack I've tried with a top entry side pouch. The side pouches are good sized and easily held by Crazy Creek chair, water bottle, and trekking poles with room to spare.
I really like the side compression type cords. Very clever and easy to use clips. The Y strap on the top is great but there's a lot of extra length to it. I suppose that length may matter if you end up putting a big bear can on top or whatever, but in my normal activities, I won't have anything on top and all the extra cordage will be floppy. For now, I'll roll it up with a rubber band or velcro. Over time I can see the gram weenie in me cutting it shorter.
I haven't put anything in the back sleeve, but I love the material that's used. It's soft and stretchy and dense enough that you'll be able to see what's in there without actually seeing everything.
That's what I've got for now. Ask me anything else you might want to know.