TUI AG (LSE:TUI) 's first quarter performance was even stronger than anticipated, according to Deutsche Bank, which repeated its 'buy' advice and 900p price target in the wake of the update. Supporting its investment thesis, Deutsche said the travel giant's stock trades at a "very significant discount" to its historic valuation and said it underperformed its main stock market benchmarks so far this year. Peel Hunt, meanwhile, remains on the fence with TUI with a 'hold' recommendation. While its shares trading on an 'appealing' 6.8 times forward earnings the broker remains "uncertain about the conversion of profit to cash". US shop Stifel holds the same recommendation, citing potential competition in the holiday market from low-cost carriers as a concern. It added: "Recent share price volatility is perhaps reflecting a UK overhang from the mooted LSE delisting – to be voted on at today's AGM."