Boutique IB, Big4 CorpFin or Gap Year after BB IB for CV

Hi,
I have recently left a BB IB (was a junior IBD analyst there, the office at my home country was closed due to bad economic conditions) and have 4 months until my MSc in Finance at LSE starts. I was planning to work for a few months and at the moment I have 2 offers: one from a small boutique IB (fairly well-known in my country, absolutely not known abroad) and one from Big4 CorpFin. Big4 salary is a joke - it seems I would make more money working at McDonalds. The compensation package at the boutique, on the other hand, is very good (3.5x higher than at Big4) but the firm is very small and is unheard of in the UK. Which offer should I take? Which would be better looking on the CV? Will it look bad that I moved from a BB IB to a small firm / Big4? Would it be better to just relax and have a gap year (so that my last place of work is a BB IB)? My goal is secure an IBD summer analyst / graduate analyst position in the UK after the graduation from LSE.
Any advice is appreciated. Thanks.