I did Jenny Craig back in 1997 after my DD was born. I started in May and was completed finished by November. I lost 24 lbs in all (147 down to 123). It was expensive, but it really worked for me. Those weekly weigh-ins were very supportive and kept me on track.
I kept it off for a couple of years, but then we had some lifestyle changes (I quit work to stay home full time, and now live out of my van taking the kiddos to all of their functions) and I slowly put back on about 20 pounds the last few years.
I've recently lost 10 pounds doing Atkins. I still would like to do another 8, but am concentrating on my workouts, while still trying to maintain my carb intake.
Good Luck.