Im running .004 taper on my longbows which includes Kennys SL. My finish tip witdth is 9/16" at the string groove.
Bow shoots very smooth and quiet. I bought a SL sled from Kenny, took me a few knocks on the head and a few calls to Kenny to get my hard head wrapped around understanding it, but I sure do like the way the bows shoot. I am going to build one and drop down to ,003 taper just to compare, but I do not think there will be much difference.