The price difference once you get into the high end version of the 13" isn't that big a difference. Both computers, the 13" and 15" fully spec'd out (with the 1TB SSD) only has a difference of about $600 USD. The Apple stores are starting to get some in stock, I got lucky and found one by just walking in the other day. Now I have to get all the adapters, RAID setup, etc. The expense really adds up quickly coming from the old Mac Pro Tower.