Shares in Next are up with events, according to Investec, despite a better-than-expected first-quarter update and raised guidance from the high street retail group on Wednesday.The broker said that stock now trades at 15.8 times current-year estimated earnings, in line with others in the sector."We view Next as a core holding, but with the shares trading on a sector average price-to-earnings rating, we believe the valuation is up with events and retain our 'hold' recommendation."Next Brand sales for the first 13 weeks of the financial year were up 10.8%, with new space contributing 2.2% to growth. This is well ahead of the 4-8% full-year growth guidance the company gave in March.The company has now raised its growth guidance for total Brand sales for the financial year ending January 2015 to 5.5-9.5%.Full-year profit before tax (PBT) is expected to total £750-790m, up 8-14% over the year, ahead of the previous target of £730-770m which would have represented 5-11% growth.Investec has lifted its PBT forecast for the company by 3.6% to £780m but pointed out that Next benefited from weaker comparatives in the first quarter, with last year seeing a particularly cold spring and Easter holiday. "Comps are expected to get tougher as the year progresses," the broker said.Investec kept a 6,700p target price for the stock.The stock was down 0.5% at 6,450p by 11:25.BC