They clocked 7min 22.88s to head home Danes Anna Lolk Thomsen and Julianne Rasmussen by almost two seconds.
Uru and Taylor dominated their final but had to scrap right at the end against fast-finishing Frenchmen Jeremie Azou and Stany Delayre, winning by only .19s in 6:40.21.
Murray and Bond recorded 6:42.97 to see off Australians James Marburg and Brodie Buckland (6:47.72) and France's Germain Chardin and Dorian Mortelette (6:48.72).
For the second time in two regattas, Haigh and Scown again trailed home Brits Helen Glover and Heather Stanning by four seconds, and the two-time world champions now know the scale of the challenge facing them at the Games.
Cohen and Sullivan roared home with a sizzling last 500m to grab second after trailing the field at halfway.
They crossed in 6:36.06, less than a second behind Norwegians Nils Jakob Hoff and Kjetil Borch.
New Zealand qualified in eight A finals last night. Five-time world single sculler Mahe Drysdale sat the regatta out with a minor injury.