it seems efficient if everything is automatic and self served, but on the other hand, there's no warm interaction with staff, so it also looks cold and unfriendly.
i would also suggest the amenities be put into the rooms, and NOT letting the occupants take them freely, people are greedy, they would just take and take, getting what they think worth of how much they had paid.
one more thing, somebody tried shuffling with our door lock in the middle of the night, and woke us in shock because of the loud banging... we really felt slight danger at that moment... it turned out maybe the man remembered the wrong room number, but already it made us nervous all through the night!!
these are just my personal thoughts, no offense.