Big 4 audit v no name CF

Hi guys,

I've just completed by Bachelors and I did a cadetship which means I've done almost 3 years of audit experience in big 4 audit. Just had an offer from a tiny advisory firm to be a senior analyst in their M&A team (think 2-3 partners).

My plan is to apply for IB grad programs in February. What would be more valuable:

a) spend the next 5 months in audit at big 4, become senior and apply for grad in Feb b) spend next 5 months as senior analyst at no name M&A advisory firm and apply for grad in Feb?

Only priority is maxing my chances of interviews come grad app time in 5 months. No other experience except Big 4 audit.