From what I've seen, DWC and aero bring the largest yields. Soil, with some organic nutes, brings about a very earthy smoke.
Proper drying and curing will bring about awesome bud either way.
email is right, the roots have a lot of oxygen from either air-stones or H2O2. In a pure aero system the roots are sprayed with nute mixes while suspended in air, provided there is a sealed container for them that is light-proof (opaque).
I've got a simple idea for an aero system.. I'll give it a go when the funds allow.
Updates later on tonight!!!
E