Although I was not offered the position, I will say that Gartner is such a great company to interview with. The recruiters are thorough and give you the sense that they truly want you to succeed - from the follow-up, coaching/preparation, and transparency of the interview process.
They place a huge emphasis on using the STAR Method of Behavioral Interviewing during the interview: S.T.A.R.= Situation, Task, Action, Results. If you're not familiar with this, please do yourself a favor, and Google what it means and how to be successful at it.