Exercise Equipment - Bender Ball, anyone tried it?

hi all, i bought the bender ball which is basically an excersize ball just smaller. it comes with two excersize routines, abs and buns & thighs. i have been doing it for about 3 days now and was just wondering if anyone here has tried it? i would love to hear if it has worked for you or if it is not any more effective than regular crunches... thanks!

ashlee