Rounds vs. squares: I've jumped both, in a wide variety of types and configurations. There's no question that a ram-air (square) parachute is a vast improvement over a round canopy when it comes to landing, controllability, choice of where you'll land, how hard you land, the ability to flare, modern design, etc. However, a square canopy also has disadvantages, too. By and large, the advantages well outweigh any drawbacks.