To save on cost some manufacturers will not heat tape the seams. This you must do. Aquaseal mixed with Co-tol is an excellent seam sealer. Neoprene Neoprene skirts seam to be the skirt of choice in this part of the world. It is a waterproof material that stretches and offers a great fit.
Neoprene has the advantage in rough weather of rebounding after being dumped on.
They tend to fit the best because of the stretch. Blindstitch is the best because it is waterproof. Mausered seams are more durable than blindstitched but are difficult to seal. Blindstitch seams sometimes unravel. It is important to catch them early with a drop of Krazy Glue for about three stitches.