the machines have been around since the 70's and have consistently targetted catalogue shoppers (ie fat/tubby sit at home mom's) claiming to build a toned stomach while you sleep.
This claim in itself is rediculous as theres no way you could sleep with electronically twitching abs!
Besides this electrical stimulation is nothing like the action of ab excercises, think about the range of motion and lack of increasing resistance, it goes against all muscle building and toning rules.
its no different to you sitting around crunching your abs without moving like some constipated dude. Fact is good abs come from low BF and good cut. You will get all the development you need from standard ab routines.
In short waste of time imo
