I interviewed for MBB and aced all of them (I got 3 offers, I accepted McKinsey).
During my 3 years in McKinsey I also supported extensively the Recruiting team with the selection and coaching process. In particular, I helped several man and women with STEM background who wanted to start the consulting career (as generalist or in Digital Practice).
I master all the prep material and I give tailored feedback both on the personal part and the case part of the interview. Everyone who I coached and referred to McKinsey got in.