Air Admittance Valve or Roof vent?

Doing a split level custom build. The plumber wants to install AAV's on some of the lower level lines, a bathroom and a bar sink. There is a way to vent them normally through the roof, it's just more work for him. Which is better? The floor above hasn't been cast and a vent can come up through the floor to meet a wall that can be stacked to the roof

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[Badger123]

AAV are fine as long as there's a main vent somewhere in the rest of the system. As the name suggests the durgo helps to equalise pressure and keep water in the traps but it can't vent (unless it fails) so you need a soil vent somewhere in the overall system to allow bad smells in the u/g o/g system to escape to atmosphere. AAV's are usually placed where its impractical to run a full height soil vent but not as a replacement i.e. they can't vent. AAV does one job = equalise pressure to maintain traps, soil vent does 2 x jobs = eqaulise pressure plus ventilating bad smells.