It is really up to the grower. Personally, I like soil. Hydro and Aero are both excellent, but the myth that they produce higher potency is just a myth, so I wouldn't put them in a "higher" category than soil, or any other medium / method for that matter (the "Dro" slang for "potent" street bud is one of my pet peeves - bud grown poorly in hydro is just as bad as bud grown poorly in soil).

Anyway - both aero and hydro offer advantages to those growing indoors obviously. Aero is usually a little trickier to set up and maintain, and for that reason I would say someone should only venture into aero after becoming familiar with hydro. Aero is also more expensive, and you can't rig up a DIY nearly as easily as say a DWC hydro. Aside from those factors, a good aero setup can be slightly higher yielding than hydro if run at peak efficiency. Sorry if that is not a lot of help, but other than examining what differentiates them (not much), there isn't really anything to say as far as one is better than the other.