There is no substitute for a professionally trained clinician with decades of experience.
A machine will never be as good as the experienced hand. Lots of chiropractic doctors never learned how to properly adjust a patient. They do not have the passion and the fire it takes to be a real healer. These 'doctors' rely on automated tools and gimmicks to practice. But a true chiropractic practitioner will use his hands to feel the subtle misalignments that are giving you aches and pains that make your day-to-day life miserable.
Don't settle for a cheap imitation. Always choose the real chiropractor that uses his hands to move the bone.