Banking vs Consulting Internship for McKinsey

I was wondering what everyone's thoughts are on the following:

So let's say I want to work at McK/BCG full time and it's not happening this year - was totally unprepared for cases and what not.

I have a IBD BB internship my sophomore summer (think Leh, ML, JP).

If given the choice between a top shop (don't have the offers but waiting to hear back/have superdays) and a consulting firm below M/B/B, what is the better option to make sure I get that McK interview?

My thoughts are that I could really strengthen my banking skill set since I would come in with a summer already under my belt but I don't want to be stuck doing banking for 2 years either and want to make sure I can get into McK or BCG.