I guess if I'd read the thread properly, instead of being distracted by the sketches, I would have seen that you said they were on A3!
It's interesting that you mention the extra freedom that the larger space allows. I use those Daler Rowney hardback A4s mostly too, (sometimes sold cheap from Cass Arts in town -£1.95 each!), it's impractical to carry anything much bigger usually. But whenever I get the opportunity I'll always go bigger! (To my shame that's true in Burger king too!