Hi Dressage Queen!
Yes, you definitely can shove in the sides and I like it best that way - it looks very feminine and sweetly old-world. If you're around my height, it's also best with sides-shoved-in if you plan to wear it on the shoulder.
I was umming and ahhing about it (was having hot flushes over the Rouge H colour in vache liegee but had to "learn" how to handle the PB style) and then I decided to play with it in the dressing room with the 360 degree view, thanks to the mirrors! Flopped down on the armchair, pushed in the sides of the bag, perched it on my lap and then caught sight of myself in the mirror.....and that was IT!
Emptied my Kelly contents into it, left my Kelly at the store to be polished and ran out into the street with my scrumptious new PB ...
Yes, I fit almost as much into the PB as I do in a 35cm Birkin. With magazines and papers (A4), I fit them in lengthwise - they do pop out the top because the PB isn't as "tall" as a Birkin - but I'm fine with that. That's the essential test for me with a work bag: must fit research papers, small umbrella, sometimes a pair of spare shoes, wallet, agenda, tissue holder, cosmetic case, mobile phone, a snack or small bottle of water, sometimes a cashmere shawl .... the PB accommodates this with the sides pushed out (I gave it a test run in the store).
So it's my alternate Birkin (great for rainy days when you need spare hands for an umbrella) and I think it's likely to be my travel bag because of the easy access and the shoulder option.
...and the push-in-push-out aspect....
Is there a particular leather you're looking for? I've also seen it in gold vache liegee (very nice), black box (my favourite leather), and blue jean epsom (I'm not a fan of epsom....)...