I currently have the late 2013 13" MBPr (i5 2.6/8/512) and I recently returned a refurbished 15.4" MBPr (i7 2.5/16/512/750M) because it had clouding on the screen when scrolling and bad back lighting, and the battery lasted only 4 hours. I'm not a pc gamer anymore, because I do all my gaming on my PS4. My questions are: 1. Should I buy the base model 15.4" MBPr with the 512GB SSD or should I retry the refurbished 15.4" MBPr (i7 2.5/16/512/750M)? I really need to have the 512 GB SSD because I need to use about 80GB (Windows updates, and other programs) on my Windows 8.1 Pro bootcamp partition. Also I want a guarantee Samsung SSD over the Sandisk SSD (The 256 GB SSD is a lottery between the Samsung and Sandisk). 2. Is there a noticeable speed difference in the from my i5 2.6GHz , i7 2.2 GHz and i7 2.5 GHz?