I've done WW and Jenny Craig. I like WW a lot more.
Jenny was ok, but the people there, I swear their goal is to make you feel like a failure in life. Aside from that the food is ok, but I'm picky so I only ate about half the choices and got bored with the food fast. I did not see the lbs drop off any faster than eating healthy and working out, so I quit.
However, my coworker has been on Jenny for about a year, has lost 40lbs and has kept it off.