Personally, i use these KA settings:
4.1 attack range
4.5 swing range
Switch mode, 1000 delay (It will help you won't get staff banned)
Targets from 1 to 2
Velocity:
I have 140ms ping, so i use 50% of horizontal velocity
If you have less ping, you should use from 65% to 70%.
All these settings were tested on my main for about two months, so i think they are pretty safe (for semi-blatant style).