Hi gents, wondered at the capacity of these before buying. Though its hard to measure do you think they are measuring flush with the top of the opening or when the internal flap is extended all the way up around the gear. Might sound like a wierd finicky question but there would probably be 5-7 L difference between either( I am guessing). I recall a buddy with a berghaus centurio used to stack gear well higher than normal and just cinch the top cover over whatever he had ro. I have a chinese made 30L assault pack about to fall apart which is just slightly cramped for my overnight sleeping kit etc which is why I am doing some internet analysis in advance.... trying to avoid a 45L at this stage.