I think flavor is a function is of airflow hole size, chamber size, drip tip bore and length, and coil positioning relative to air holes. I can set up most of my RDAs to get very similar flavor and vapor performance, what makes me prefer one RDA over another is convenience of building, airflow adjustment, juice capacity, and leak resistance.
The Magma is one of the easiest to build, but the airflow ring can slide around and the top cap is threaded, which can make re dripping a hassle. The Tobh is my all around favorite because it's easy to remove the top cap and the air flow large and the flavor is great when you place the coils right next to the air holes. The Derringer is my next favorite due to it's small size and intense small chamber flavor.
The Marquis is a dream to build and is very leak resistant.