Actually, ASUS's lock free is not unlocking multiplier completely AFAIK. Here's what I know about lock free (or whatever it calls).. You can select two multiplier, 14x or original multiplier. 14x multiplier is useful when you have high performance RAM that can do 1:1 with high FSB. Even if you don't have high performace RAM, you can get more FSB since multiplier is lower. For example, like 230*16 = 3.68GHz vs. 262*14 = 3.668GHz. 262*14 has slightly lower real clock, but it is no doubt that the second one will perform better since its FSB is way higher. So, how it can be used is opposite to what dashiki said.
Yes, it is useful for some, but totally useless for some as well.