Should I make the switch to a BB from a small boutique?

Hi all.

I am new to this community, so bear with me here. I currently am a recently promoted Research Associate that works at a boutique firm. The work is great, I have made some lovely friends, and the work life balance is actually amazing for sell-side research. The only downside I have right now, is the person that I work under has been very difficult to work with since they replaced my old boss mid-last year. We have had countless run-ins, and I have a feeling the firm could be looking to get rid of them as their performance since joining has been quite underwhelming. 

Anyway, I digress. 

Last week, I got a call from an old colleague who is now the head of research at a BB. He wants me to go over and work with them. From what I hear, my new boss, if it all was to go to plan and I went and worked for them, is very old school and doesn't have good people-skills (if that makes sense). So again, this could be a bit of a challenge... But nevertheless, having the chance to work at a BB would be a dream and I'd be willing to look past this.

So, my question to you is what would you do in my shoes.

 Would you stay at the boutique where you are well-appreciated and have a good WL balance (for Research) yet are having some conflicts with your boss at the moment? Or would you make the switch to the BB where you know your new boss is a bit cold, but could be willing to look through this given it is a BB.

Keen to hear your thoughts!

Thanking you in advance.