From what I've read, no machine/device works better than a plain old ball. Are you pulling on your neck when you do crunches? Have you tried other types of ab exercises such as planks?
I own Ab Revolutionizer which works wonderfully. IF you actually do it everyday that is At least 3 minutes a day.
I also love old fashioned walks! Walking helps you look and feel amazing.
I have a ball and it really works. Don't pull on ur neck cuz I have neck problems to but if you use the ball it relieves less stress on your neck if you use the ball the right way.
I agree, do some planks. They shouldn't hurt your neck.
I've learned from years of experience with buying equipment--don't do it.
It winds up at The Goodwill store or in a yard sale (or just sitting around collecting dust).