I'd really like to know what you do to make a 2 year Macbook Pro upgrade cycle worth the cash outlay. Performance updates have been really incremental between r

I'd really like to know what you do to make a 2 year Macbook Pro upgrade cycle worth the cash outlay. Performance updates have been really incremental between releases for the last while. I do some serious machine learning and DSP development (except for deep learning, but an upgrade is not going to help with that) on my early 2013 rMBP and I feel bad asking for an upgrade although I could probably get one, because there is really nothing wrong with my machine. Maybe when a 32GB version swings around...