Peel Hunt has upgraded its rating for brewer and pubs group Marston's from hold to buy after like-for-like (LFL) sales growth surpassed expectations in the first half.Managed LFL sales increased by 3.5% in the 23 weeks March 10th - Peel Hunt had estimated a 3% rise. The broker says that trading in the most recent seven weeks was marginally positive, compared with sector peers Wetherspoon (-0.7% for six weeks) and Restaurant Group (-2% for eight weeks)."Marston's selection of high-returning investment projects is such that it should improve its market position. This strong Q2 result gives at least an indication that the value strategy is indeed generating outperformance," said analyst Paul Hickman.The broker has today raised its pre-tax profit and earnings per share forecasts by 2% for 2012 and upped its price target from 100p to 114p.The stock was trading 1.46% higher at 100.9p just before midday on Wednesday.BC