Essentially “My Best Friend’s Wedding” with a dark side. Jason Lee and David Schwimmer (“Friends”) are best friends, even though their outlooks on life are totally divergent: Schwimmer is a womanizing sportscaster, while Lee is a sensitive writer with a broken heart. Mili Avital plays the woman in the middle as Lee’s editor who gets set up with Schwimmer and it’s “love at first sight.” Naturally Lee and Avital are the ones really meant for each other, and things really get complicated when Schwimmer asks Lee to try to sleep with Avital to test her. Schwimmer plays his two-dimensional egotist with the right degree of testosterone, and Avital is a sensual delight, but Lee, who was so hilarious in “Chasing Amy,” is unconvincing as a sensitive romantic. Bonnie Hunt adds a dicey performance as Lee’s publisher, and the beautiful cinematic framing of Chicago, help keep this romantic comedy a notch above the formula.