I always found access very easy /good ... access from the top and side , plus the tier can be removed in a jiffy.
Ive pulled my bag for literally hundreds of miles by foot and used it on public transport. I pull it up and down stairs at train stations no problems .
I use it packed to the brim , but also with minimal gear from time to time . It always stays upright , never topples .
Sure , when i get a lift , people whinge at the size of my bag , but otherwise, no complaints. ....and like i said , it seems they have improved it further .
Btw , im talking about 8 yrs worth of experience using this same bag .