If it helps: I love my C4's in the waves, best I tried yet. I tried the Catalyst but prefer C4. I have 2010 - 5, 7, and 9m C4's I weigh 75 KG, and only use surfboards. Normally a 5'10 surfboard or sometimes a 5'4 Underground Freewave for blasting. I always use the 9m on 20m lines. 9 goes from about ...