By Peter Wahlstrom, CFA With its widely recognizable PointsPlus and ProPoints programs, Weight Watchers ( WTW ) has established not only a successful weight management program but a business model that generates substantial cash flow. We like the long-term prospects of this wide economic moat firm, but we acknowledge that the next few quarters could be choppy, given recent miscues. Specifically, in the first six months of 2012, Weight Watchers reported hiccups related to its emerging corporate and international businesses, and management has drawn criticism over the timing of its $1.5 billion "modified Dutch auction" tender offer. Since mid-March, shares are off 36%, compared to a 1% drop in the S&P 500 Index. Shares currently sit in 4-star territory at a more than 30% discount to our $77 fair value estimate and, at 11.6 times our 2012 earnings per share estimate, we view Weight Watchers' stock as a solid medium-term idea for investors.