Aero IF it is a large tube or a very well aerated reservoir small tube, followed by ebb and flow and lastly the DWC. If the reservoir water is not very well aerated on the small tube aero the efficiency plunges once the root mass gains size. Roots laying in low DO water die quickly. Even with high DO water the fact still remains that even cool water holds only small amounts of DO and the oxygen diffuses poorly. A small tube aero can actually perform worse than a DWC if the root mass is large, the water flow slow and the water DO low in the tubes. Many aero tube systems perform worse than ebb and flow system once the plants gain some age the ebb and flow systems maintain better root masses then the sad roots in a poor small tube aero system. Lots and lots of small tube aeros with nasty, rotting, brown roots towards harvest time or even earlier. You will find quite a few hair roots on mature plant roots in an ebb and flow system, very few if any in a small tube aero system.
A DWC is also very dependent on unnaturally high reservoir DO and no water can hold large amounts of DO and nearly the entire mass of the roots in the DWC system area entirely in the water. A large tube eliminates most of the problem of roots laying in low DO water A deep chamber aero eliminated the problem of DO all together and the level of the DO in the reservoir really has little effect on the amount of O2 taken in by the roots. An Ebb and Flow is limited through the fact that most ebb and flow have fairly small air pore space so oxygen is more limited than in aero system. An ebb and flow is not dependent to any large degree on high DO reservoir water however, unless there are rock wool systems that tend to become water logged the rock wool as they drain well.