Just from what I've seen the 2.0 cams would give slightly better performance and slightly smoother draw. I had one earlier this year with 1.5 cams and could not get the draw length short enough for me. I shoot 26 3/4" and although the S-5 was listed at 26.5" to 30+ the shortest I could get it was 27 1/4", that after adding 15 twists to the string and 5 less twists out of each cable. This years model is listed at 27" on the short cams. Go figure.
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