As others have noted, the lock-off does have a double, lockable door to the adjacent studio unit while a straight one bedroom just has a wall there. Thus, a straight one bedroom "should" be quieter.
OTOH, if you are considering a dedicated two bedroom as compared to a two bedroom lock-off. In addition to the possible advantage of having the occupants in the studio portion being able to lock-off from the main part of the unit, there are a couple of more advantages to a lock-off. There are individual temperature controls in the studio and the main portion, which might be helpful if not everybody in the group agrees on what is the "corrrect" temperature in the unit. Also, the lock-off studio will have its own toaster, micro wave and coffee maker, whereas a straight two bedroom unit does not.