I've been using Queal during tight spots in my schedule the past week, seeing how it fits with me and my stomach. Even though its design is complex, it's ultimately a simple product experience; that's the point. I'm trying out a few flavors, and they all seem fine to me.
The one thing I'd look at is the Queal flask. It's light, which is good. However the seal isn't too solid, it's thin and doesn't always hold tight during shaking (and I'm not heavy-handed), and the carabiner is pretty cheap and something I wouldn't use anyway (does anyone really hang a flask of meal shake from something?)
I reckon you want your users to be consuming all their Queals in the flask, so I'd be tempted to beef it up a bit quality-wise.
Otherwise, it's a solid help in my life, and I'll be upping my order next month, maybe to having 50% of my meals in Queal form.
