** Restaurant Brands's U.S.-listed shares down 4.7 pct and Toronto-listed shares down 4.3 pct, set for their worst day since early January
** Company reports comp sales at Burger King in U.S. and Canada falls for second straight quarter; overall comp sales growth at both Burger King Tim Hortons slows sharply
** "In light of McDonald's more robust numbers, it is disappointing that Burger King did not push into positive territory," says Neil Saunders, CEO of research firm Conlumino
** However, Restaurant Brands's Q3 profit, revenue beat analysts' estimates, which Stephens analyst Will Slabaugh says is "sufficient"
** "QSR remains one of the few restaurants where investors can easily draw a multi-year path to margin improvement and earnings upside": Slabaugh says
** Up to Friday's close, U.S.-listed stock had risen nearly 26 pct this year; hit 52-week high on Sept. 1