I have several scores complete on sibelius> I just aquired Logic8. is it a good idea to install them both on a new macbook pro, or will this severely slow me down..?

also, being pretty familiar with sibelius, and not at all familiar with the logic8, any suggestions on where to begin. I need to get my sibelius scores onto logic8 to make a film score.....my first attempt at this.....so

'all help is welcome here.!