B-School resume: MO associate promotion or lateral to product group?

Which would look better to strong B-schools on a resume for work experience: being promoted in a more middle office role to associate or successfully lateraling internally to a product group that is known to be strong (eg. M&A/LevFin) before applying to schools as an analyst. FYI by middle office I am referring to an analytically/modelling heavy credit/corporate banking role that does interact with clients at times (eg. I've traveled to bank meetings and client headquarters as an analyst) but is not a coverage or traditional product group. I am in my second year, and with strong performance reviews have received feedback that I would probably have the ability to take either path.

My thinking is that while of course a promotion is looked upon favorably, if my end goal after business school would be to transition to a BB/EB in New York (currently at a lesser non-NYC bank that is certainly widely known but not a BB), would it look better to be associated with a more "prestigious" and recognized group of the bank?

Appreciate any opinions or different lines of thinking.