Lit Review as Writing Sample?

[Carlpolisci]

Hi,

Just putting together my application for PoliSci PhDs and try to decide on the writing sample I should submit. Since I'm an international student, I really only have two english samples: 

a) A lit review

my Master's capstone.

Generally, I think the lit review is written stronger, however it's  a lit review, so it doesn't really prove that I can discuss a thesis, etc etc. 

My capstone would do that. On the other hand: I have to boil it down to 10-15 pages anyways, so there won't be much left of that either. 

So my question is: Is a literature review a good writing sample or should I try to make the capstone work?

 

Thanks!