Using your System with a disposable bag will add protection to your motor and the maintenance will be less effort, since all the debris will be held in the bag. The washable permanent filter will stay cleaner and will add to its longevity.
Using your System without a disposable bag is not issue. You may have to clean your canister and permanent filter more often , but if done properly, you will assure no debris can reach the motor and assure it's maximum performance