I've looked at comparison charts of the processors, but really have no good understanding of what distinguishes the 'ivy bridge' vs 'broadwell' (?) architectures. Is it worth it to buy the current MacBook Pro Retina 15' with 2.5 GHz quad core i7 with 16GB RAM and 512GB SSD and AMD Radeon R9 M370x w/ 2GB GDDR5?
I currently have the mid 2012 MacBook Pro Retina 15' with 2.6 GHz quad core i7 with 16GB RAM and 256GB SSD and NVIDIA GeForce GT 650M w/ 1GB GDDR3.