i have used 22/18...18/16...and 16/14.............they are all about the same. in barcalona i snapped my 14t cog and sam from drop bikes kindly gave me a 15t cog , them guys sorted us out so much:p. ever since then i have used 16/15 with 170 echo cranks. i couldnt go back to 16/14 now, but its just what people prefer, i couldnt say all you who dont run the same as me are wrong cause its the same with tyre pressures, personal preference.