wensz

Hi @Lllok, previous applicant speaking. The first thing I would do is definitely make sure your verbal is competitive - reading from your post you should be able to get in the 165 range...which is great.  As for quant, I know a lot of people with mid Q 150's who have gotten into top programs - although not anyone specific to Columbia phD with a sub-160, so I don't want to speak to that.  Honestly, if you're already expecting around 155, I would recommend to put in around 20-30 hours give or take (I know it's stupid, but actually not too much time!) and try and get it up to around 160.  I think it's definitely possible, and you're already close, so my recommendation is just to make the push.
Another considering is the AWA.  For me, I viewed the AWA as maybe more important than what many admissions websites state.  Though it's not demonstrative of your critical thinking or research skills, which your statement and sample should speak to, I think it does show that you have a good ability to argue clearly in writing.  In my opinion, if your V is 165+ and AWA is 5-6, I wouldn't worry about Q -- this should definitely be alright for almost every university.  But we never really how these things are weighted, and if a department explicitly publishes their recommendation, I believe it's best and safest to match them/get as close as possible.
 
Of course this is just my own take on it.  Hope it helps!