I have a 2014 rMBP 15” with dGPU, 2.5 Ghz Quad Core i7, 16GB RAM and 1TB SSD. For the most part it is adequate for my use. It is taxed most when organizing a large photo library and occasionally when manipulating or OCRing large PDFs. If I were to try to replace my old 15” with the 13”, would I run into performance bottlenecks? Are the current 13” MBPs faster than my older 2014 15”? Will a 13” today be an upgrade or downgrade from my 2014 15”? If I get the leaner 13” rMBP of today, will it be about as powerful as my older, bulkier 15”?