[pinneycolton]

I second this. I'm writing this on a late 2011 MBP w/8GB RAM and an after-market 1TB SSD. I use it primarily for developing and testing data-driven applications (big data, medium data, small data). I occasionally run Windows and Linux VMs when my development work demands it. This "old" MBP is my primary machine.

I don't have any major performance issues to this date, at least not for my primary use of this machine. I typically run Netflix, Hulu, or some other media while I code, and I actually have more issues with Flash video running in the browser than anything else. This is generally tied to Spotlight reindexing. Killing the index and allowing the machine to rebuild it from scratch usually resolves my issue. But, I digress...

Take the time to understand how your work utilizes machine resources and buy the best machine to get the work done. It might not even be a MBP.