its close between 123a-and 4a. 5 and 6a's dont come near as close. of course every weight has a stud or so, but look at 123a, 145lb of 4a, 152lb and tell me theirs even near as tough as brackets in 5 or 6 a. id have to say 4a, a majority of wrestlers from 4a go on to college and wrestle. ex matt murry, trevor charbenue(spelling), bryce abbey, ryan phillips, buea tillman,austin devoe,and others recently.