This is a great device with many positives, and very few negatives.I work in a call center sitting all day, and I get a very tight knotted muscle pain running up and down the left side of my spine and into my neck and shoulder, a pain that often makes it very difficult to sleep or relax. I have tried many things ranging from expensive 1hr and 2hr deep tissue trigger point massages, cheap vibrating back massage devices and rolling shiatsu massage chairs, chiropractic adjustments and tens unit devices. I have tried most over the counter medicines and quite a few holistic herbs to relieve inflammation and nothing has worked long enough to make it worth the high cost.Once I got married I could no longer afford weekly chiropractic visits or monthly massages. (which only kept the pain under control but did not eliminate it)I started looking online and read tons of reviews. Finally it came down to two devices, this one and the Thumper Percussive massager. The Jeanie Rub looked exactly like something an old chiropractor had once used on me, and I recalled it had relieved my pain for a couple of days. Ultimately I went ahead and settled on purchasing the variable speed model. I admittedly felt a tinge uneasy about the high price tag, but still felt hopeful that it would be worth the high price if it worked. It would be an investment if I no longer had to spend 120+ a month for massage and chiropractic visits. I was still very skeptical.The device came on time (next day) and I tore it open and examined it. It was heavier and bigger than I had imagined, but solid and well built. I hurriedly plugged it in and turned on the dial switch. The device began to rotate in a way that my wife compares to a car buffer. I first tried it on my leg, then on my brothers back then finally on my back. My back sank into heavenly bliss.Unlike other massage machines this really had the power to sink in to my stiff muscles and go "deep" enough. I felt my muscles relax almost immediately. This machine has a ton of power. Normally I require deep tissue with tons of heavy pressure, but the oscillating 4200RPM action gets in deep without applying much pressure. I was soon glad that I got the variable speed model, as I found the fastest speeds worked great for me, while most others preferred the lower RPM speeds.I love showing people the jeanie when they come over, it's so unique. When using this device on me, my three brothers, and most others, the initial reaction you get is a deep relaxing "aaahhhhh" as your muscles melt and your cares drift away. " I want one," and "thats awesome" are very common responsesThe best part about having this device is that it works consistently when I need it, and within about 10 or 15 minutes I am pain free lasting for about a day or two.I soon found myself asking "what else can this "Jeanie" rub?" Now, I use it on my head for a scalp massage. I have used it on my face and jaw when I had jaw muscles locking up, on my legs abs and chest and feet (very nice on feet), and just about everywhere else you can think of. Anywhere that you want to feel deep vibrating relaxing pleasure.The more I use it, the better I get at picking the right speed and using the right pressure and movement techniques for the best overall feel.Now, I will mention the few negatives I can think of.The device can make your back feel itchy after about 10 minutes of use. I had to use it a while to get used to it. Like a really bad almost unbearable itch. My wife really hated it at first, and only after a while was I able to convince her to use it long enough to get past the itching feeling. (my guess is it has something to do with blood rushing to the back area) Even now she does not like this nearly as much as I do. Most the guys that have tried it on have liked it. (I personally feel like the itching is a small price to pay in order to have my back pain relieved, and found the itching goes away the more you use it)Also it is big, and pretty heavy. I would probably use it twice every day (in the morning to loosen up and at night to relax) but it to hard to use it on yourself, (when working on the back) so someone else will need to use it on you. I took it on vacation with me in my checked baggage, the TSA must have thought it looked suspicious because they searched my bag.Also my wife really doesn't like the vibrating feeling it produces, it bothers her hands, so she doesn't enjoy using it on me and I feel kind of guilty when I ask her to use it on me. (my wife is one of the few people who had this complaint)Ultimately this device has helped a lot, and in my opinion was worth the high price tag. I have not been to the chiropractor once since getting this device. I am still interested in saving up for the Thumper Massager, as I am hoping it will be something I can use on myself without assistance. I am also hoping that my wife will like it better than she like this.