Reply to Ableton library location

Looking for advice on setting up ableton. I have live 9 suit installed but have not yet uploaded the library. I dont have a good internet connection atm so I didnt download my sample library from 9 upgrade, what I do have is the CD's from my live 8 suit pack.

Question, I have a new macbook pro with 500GB storage, of that 500GB around 270GB is remaining. Should I store my library on to my lacie USB3 external hardrive or my internal drive?