I withdrew my application right after returning home from my all-day interview, as I had an awful experience. First, they squished 6 interviews, including one with a written exercise review, and one with an excel-based live exercise, all in one day. I thought this was a bit excessive for a company of their size and profile, but I was well-prepared for it regardless. In fact I admired their pride in being "hardcore" with candidate due diligence, and went in expecting high-quality, stimulating discussions.
However, the actual interviews (mostly) seemed inane with a largely unstructured set of stale questions, seeking canned answers. Barring a couple of interviews who were actually amazing, all other interviewers seemed very transactional in their approach with no real curiosity to drive a 2-way discussion. The worst of all was one of the "higher-ups" who kept asking about "Value Proposition" in abstract terms (such a 1990's and/or Consulting worldview, btw!), with little appreciation for any data-driven approach. When I challenged his views and presented alternate perspectives, he seemed visibly agitated, and got a bit aggressive. Towards the end of his interview (which was my last one for the day), he even went to the extent of hurriedly ushering me out of their premises stating that he was running late for some other engagement. Forget about offering me water or an opportunity to use their facilities, he didn't even give me enough time to gather my belongings - I was ushered out with my half-open bag on my shoulder, with one hand clutching my laptop, one barely holding on to my lunch box and my phone!
If his behavior was a reaction to my challenging him, then he was clearly a megalomaniac who prefers "yes men" that would never challenge him, and I feel sorry for the employees who have to put up with such a toxic top-down culture. If his behavior was because he was busy, or because of other reasons unrelated to me, then it still reflects an utter lack of basic values. Either way, this is not the kind of place I would like to work at.
With all that said, I'd like to give credit where it's due - the in-house recruiter was a fantastic chap who cared enough to contact me to gather my feedback when I withdrew my application, and apologized that I had a bad experience. Also, a couple of the interviewers were wonderful folks - those interviews were pretty engaging.