I bought the Ab Roller Plus after the product made its way to stores. This is the original promoted by actress Brenda Dykgraaf. Today there are many different ab machines available and Ab Roller has variations of the original for sale. You can still get the original at re-used sports shops, on eBay, and at garage sales for between $20 and $60 dollars.
Overall, this machine is pretty well put together. The headrest and pads are durable and have lasted through years of use. The steel tubing is solid. The bolts holding the tubing together do tend to back out and need tightening occasionally. The pivoting feet are firm and have never hung-up or made noise.
The Ab Roller Plus works as it says it will. It provides neck support and keeps your head and neck in an aligned position with your spine. For what it is, and if you use it as you should, you will get results.
You can do several ab workouts with the assistance of the Ab Roller Plus: The basic crunch, side lat crunch, raised leg/knee crunch, and variations of each changing your hand/arm positions. Full sit-ups can be done also.
Believe it or not, you can do two arm exercises with this machine too: Duel Bicep Curls and Reverse Duel Triceps Curls. The weight of the Ab Roller Plus is enough to provide a workout without adding bulk (perfect for gals). See photos above.
This machine is best used on carpet or a mat because it slips a on hard floors.
The only big problem I have with the Ab Roller Plus is its bulk. You cannot store it easily and there is no way to compact it without completely disassembling it. Otherwise, I have been happy with my Ab Roller Plus for the results it's given me.