Try Vic Firth's "MS4 Magnums" or Vic Firth's "Ralph Hardimon Hammers." Either stick will give you a workout you will never forget.I don't have any problem with the stuff Pocket f.o.g. mentioned, but when I practice Bill Bachman's exercises (e.g. doubles) on a pad, I use the heaviest, fattest sticks I have, then switch to normal sticks when there's improvement worth moving to the drum set.