[throwawayme174]

From the point of view of someone who is much like the candidate you interviewed(could be him too!) here are some factors you need to consider before making a decision.

a) What is the size of the team that he is going to be collaborating with when writing code...If its just him or a team of two people..He could be an asset since annoying people are mostly very confident and motivated and when working alone they can be very very productive (Case in point:Linus Torvalds).But then that works the other way too.

b) Is someone smart going to be mentoring him...I feel like he needs a mentor or someone who he can learn from...the annoying attitude is mostly just a defence mechanism...once you can prove that he has something to learn from you or his boss his annoying behaviour will most likely go away.(Case in Point:Matt Damon in Good Will Hunting).

c) The culture of your company...Are you a company where you focus more on stability or you focus more on creating ....As the Steve Jobs says in the movie ,Pirates of the Silicon Valley,"Creation is messy".....and needless to say people who dont give a fuck about the status quo or what you think about them are an essential part of that mess.

d) "Not sure if feedback to him would change those things (they're hardwired/part of his personality)"...I dont know if this is an assumption you are making or this is part of the question.....Feedback to him could certainly change things...especially if you point out to him what parts of his behaviour are annoying in particular and why exactly is that counter-productive to the company and himself too.Smart people are also reasonable and if you have good enough reasons to support your suggestions he will acquiesce and will respect you for your candor.

EDIT1: Grammar EDIT2:I just got a rejection email from the company I interviewed at.So I deleted the personal note.The other points still hold.Good luck!