10:1 is definitely easier to tug on. However, the I20 requires more sheet motion than the F18 when easing in a gust to keep the boat moving well. On the F18, you can let out an arm's length (or maybe one wrap) on your hand to ease enough with 10:1. On the 20, however, with that monster sail and 10:1, you have to let out just a little more sheet such that you have to do one hand-over-hand to get it back to good trim once the gust is gone. With the 8:1 on the 20, you can do it with one arm pull, avoiding the slow hand-over-hand and have more effect on the sail trim. Yes, the 8:1 is harder to pull, but it's more costly time-wise to pull the extra sheet required by the 10:1 (and is usually the crew's problem anyway ;-)). This is purely my opinion but I've heard it echoed on the beach by several other teams.