SM offer or stay on sell-side?

I received an offer to a small LO (<$500mm). My goal is to break it to the L/S MMs. I am currently in ER with less than 2 years of experience.

1) Do I stay with my current ER job and apply to MMs in the future or will the buy-side experience at the small shop help more with recruitment, keeping modeling tests, case study, technicals, etc. aside. 

2) Is there a significant difference between the two for M7 considerations?

Basically trying to judge if switching to this buy-side role will actually make it worse for my career opps, given the small size.

Thanks.