I'd pick Bruna's only because I've had it, and in that old-timey goombah environment with an double espresso, it's just right.
But the best tiramisu I've ever tasted was not far away from Bruna's. On Taylor St., before Enoteca Davanti--probably mid-1990's--there was an Italian restaurant in that space whose name I can't remember. But they served a glorious tiramisu in a goblet. Perfect balance of ladyfingers, cacao, coffee & marscapone. I still think of it.