I took a short trip with my local backpacking MeetUp group - 11 folks and 3 dogs total to Feather Falls near Oroville Calif.
Trip report is here
Although I worry a lot about stuff sacks making a break for it by squirting out sideways, this trip I decided to tempt gravity and just use my gear's native stuffsacks instead of using my DIY sacks with lashing points.
I cranked down on my ladderlock-equipped straps and it looked pretty good. For the trip in, I went ahead and deployed the Packa in raincover mode, just to contain any potential escapees.
For the trip out, since I had eaten all my food, I had a convenient spot to store the Packa so Molly went nekkid. The load was solid and did not shift at all. I tested it by picking it up and shaking it violently over my head. Our trip leader was impressed by how easily I did that - a testament to my increasingly light loads.
I used two of Mac's pouches to contain little bits and pieces, and on this trip I realized that my 'kitchen' (the vertical light brown sack at the top) could be held firmly between those pouches. Prior to this I had had it horizontally and it bounced and danced around quite a bit. This stuff sack does have a lashing point, since it holds my cookset and Caldera Cone so it does not squish at all - hence is prone to escaping the cinch straps.
I tried mounting my hydration bladder on the hipbelt and that worked well enough that I think I'll go ahead and make two holsters: one for each side. Prior to this, I had carried the hydration bladder in Mac's hydration sleeve vertically between the pouches.
There was a whole lot of gear chat on this trip (fun!) and the MMP generated a lot of interest. One person took photos of it from all sides - if I can get copies of them, I'll post them further down this thread.
Thanks again Mac, for a great piece of gear!