First, I'm really happy to see a onebag offshoot community happen here outside of Reddit!
Figured we should get this community going by posting what our go-to bags are. Why did you choose that bag? What do you like about it? Anything that could be improved? Any other bags you're eyeing?
My current go-to bag is the Osprey Fairview 40. It's incredibly comfortable and suits my body (I'm very petite) better than my previous bag, which was the RedOxx Sky Train. For me, the issue with the Sky Train was the lack of hip belt for heavier loads, especially when it was packed full (38L capacity). I also wasn't too happy with the organization of the Sky Train either, I think I much prefer having one single compartment and relying on packing cubes.
I was so surprised how comfortable the Fairview was when fully loaded. It didn't feel heavy at all. I guess that's the benefit to having a pack that fits your torso length, along with a proper hip belt!
I got the Osprey Nebula 32 L this year, and after a successful one-bag holiday in Vancouver it's more than proven itself to me. Just enough compartments to stay organized, but not so many that it's overwhelming or that it cuts into usable capacity.