Hello, I'm in a little predicament, I recently bought myself a macbook pro 15": mid 2012 non-retina for $1100 off craigslist. The original owner bought it from macmall four months ago. (specs below). Everything is running great, laptop is in excellent condition etc etc. I bought the laptop primarily for coding, I'm not a gamer but I do like having my computer run smooth. My plan was to upgrade to a SSD and add more RAM. Question: Instead of upgrading to a SSD & RAM, should I just buy myself a macbook pro 15" retina? the 2012 retinas have been going for about $1300+ on craigslist lately (example below). What do you guys think. is it worth it? is the performance that much different? My laptop Original Price: $1,499 Bought for $1100 Mid 20212 non-retina (Applecare eligible) Apple MD103LL/A 15.4" MacBook Pro quad-core Intel Core i7 2.3GHz, 4GB RAM, 500GB 5400-rpm hard drive, Intel HD Graphics 4000, Ships with Mountain Lion (Turbo Boost up to 3.3GHz) Potential Craigslist buy: $1500 Macbook pro Retina 15" 2.6GHz Quad-core Intel Core i7, Turbo Boost up to 3.6GHz 8GB 1600MHz DDR3L SDRAM 512GB Flash Storage Any feedback is greatly appreciated. Thank you.