Actually, you could employ all 3 methods in this case. Regular topping,and fimming will stop top growth and encourage lower branches to grow up, and LST trainig, can definitly your best friend if you want to keep em' low. Bend those babies over and tie em' down, again and again, letting lower branches pop up high enough to make a cola bud. You would be surprised how well ost starins react to that type of training. Good luck man!