If you think you can improve considerably and eventually score 175+, then waiting is by far the better option.
What kind of comment is this? Are you serious? Eventually score a 175+!? What if I only hope to score a 165 (up from a 158) and that's why I'm waiting until December? I hate how so many people on this site are so unrealisitc about scores. I mean after all, according to this comment, I must be an effing idiot to try and apply to law school with anything less than a 170!