Boutique consulting firm vs. Deloitte M&A team
I am aiming for the Big 3 consulting firms upon graduation.
I am taking this semester off and I got a position for a research analyst at a boutique consulting firm. It's for 3 months and I'll probably gain a lot of hands on experience during this internship. They told me to start working next Monday and I told them I will go.
However, today I had an interview for a research assistant position at the Deloitte M&A team. Although it wasn't for a consulting position, I had to do a case study and ended up performing poorly on it. However, my interviewer still liked me a lot and told me that he wanted to see me one more time. This is an unusual case because there usually are no 2nd interviews. I guess the interviewer wanted to give me another chance...
The problem starts here: Deloitte's interviewer told me he will contact me on Monday and will schedule another meeting, which will be held on a weekday. However, that is the same Monday I start working at the boutique consulting firm. I would have to lie to the consulting firm in order to attend the 2nd Deloitte interview.
I have 2 questions: if I am aiming for the Big 3, would interning at the boutique consulting firm or Deloitte M&A be better for experience/resume?
And also, what is a good excuse to the consulting firm when I go interview with Deloitte? Certainly, I don't want them to know I am considering to stop working until I actually get the Deloitte intern position.
Advice would be of much help!