Initial notes:
– This alone will not give you abs. Only low body fat percentage will do that, which is done by proper nutrition and burning fat via exercise.
– The Ab Carver is simple but intense. I would not recommend this if you are moderate to severely overweight as it is puts a lot of weight on your upper arms and you may not be able to do it properly.
– Read as much about the human body and how it works as you can. Understanding your body is a biological machine that requires proper maintenance to be the way you want it to be is half of the battle.
I have been using the Ab Carver for 21 days now, and just completed the initial training circuit it recommends before increasing the roll distance. In short, this little piece of equipment gives you a high intensity workout in a short amount of time. You'll be working arms, back, shoulders, and most importantly your core. After one use you WILL feel it.
When purchasing, first thing you'll need to do is get on the Ab Carver website and print off their instructions and workout schedule. It is ridiculous they do not send this with your purchase, but its likely a ploy to get you to your website. The workout consists of alternating days 3 sets of 10 reps straight out, with 3 sets of 5 for obliques. This increases each week, until day 21 where you will start pushing out farther.
Quality of the machine is pretty high. I haven't had any problems with the spring inside, and the handles are pretty firm. The pads they send for your knees are pretty flimsy, but again I never had an issue with using them. Does this machine work? Yes. I am already getting defined upper abs, and working on losing my remaining belly fat to show off the lower abs. I can't stress enough the importance of body fat percentage for abs. If you don't combine this with a caloric deficit and cardio, you will never get visible abs. Running, jogging, biking, anything getting your heart rate up is good for this combined with proper nutrition.
I can't tell you how long or how hard you'll have to work to get abs, it can literally take months and months depending on your start point. My advice is not focus too much on gaining that "perfect body" but instead focus on getting a healthy, fit body. For me, I'm on a 60 day plan alternating between running and strength training, with a high protein diet and overall 500 calorie daily deficit. This machine is only a small piece of the overall puzzle to getting in shape, but use it correctly and it is a good tool.
Some final tips:
1) Develop a plan. You are much more likely to fail if you don't set up a schedule for exercise and also get a meal plan set up.
2) Push through what I call the "Disappointing" phase. You're going to be working your butt off, look in the mirror in 10 days, and feel sad because you aren't ripped. Getting a highly fit body will take at least several months, maybe more depending on your start point. Don't expect it after a few hard exercises.
3) Be realistic. The people you see in the commercials for these types of machines are professionals paid to have an almost unsustainable low body fat. Aim for being healthy and lean, as being completely ripped will likely be more time that what you'll want to put in (myself included).
Thanks for reading, your new body begins with the first roll!
*DAY 90 UPDATE* Having continued using this every other day as per the schedule, I am now at the max possbile roll distance and difficulty and have been at this level for several weeks. This has certainly increased my core strength, and has given me some nice visible ab outlines now that my body fat is sub 14%. Machine still works perfectly.

Has a comfortable grip & very stable to use. The built-in resistance helps to create a smooth operation.

This ab roller is awesome—much sturdier than the cheap ones I’ve used before. The wide wheel keeps me steady, the spring gives just enough push back, and the padded handles are really comfortable. Definitely worth it for quick core workouts at home. A great tool for building core strength at home. More stable, comfortable, and versatile than standard ab rollers, and the resistance feature makes it accessible for both beginners and advanced users.