I won't comment if other machines have not been used. I have been using ageLOC slimming beauty Spa, and I have not felt any side effects. Nuskin ageLOC slimming beauty Spa is designed with advanced patented technology. Micro-current can be adjusted according to the skin condition, and with specially prepared repair products, it can suck away hidden oil and dirt and push beneficial ingredients into the skin at the same time.