I have been thinking this way in the past, but I have come to realize I was comparing apples with oranges. Most of the soil products I smoked were from experienced hobbyist that didn't do large scale crops and were growing for themselves as well. Most of the Hydro products I smoked were commercial suff grown in large crops by people who probably smoked something else.
After reading and educating myself, I have come to the conclusion that if you know what you are doing and you care for your plants, you can grow good tasting stuff in both. Soil is easier to me and hydro seems more complicated and does intimidate me.
My opinion is that, all other things being equal, hydro will simply produce bigger yiels per plant and per sq. ft. than soil.
It is also my opinion that improper drying and curing is one of the main reasons for harsher smoke and bad taste.