It has been my experience that the continuous loop strings are a bit noisier, than the Flemish. This is due mostly from the wrapping of the Flemish string being softer, and the continuous loop being harder, due to the wrap on the loops.
One sure way to cure the noise on a Flemish string is to dip that part of the loop in lacquer thinner. It removes the wax, and will greatly silence the string, as it becomes softer. Some guys will put mole skin on the curve of the limp to quiet a loop string, I have mixed results with this method.
Continuous loop is an easier string for most novice to make, and as afar as which is better. Well to me one is as good as the next, with the continuous loop lending it self more to the the twisting up for tuning, or down to get the brace height correct for a given bow, and shooters style.
A Flemish twist string, which I shoot, can only be un-twisted so many times before it is in danger of coming apart. Be mindful of which way you go when adjusting it.