I decided to take the step to my MacBook Pro mid 2011 and it's just great. Besides Apple makes the transition so much easier: installing the OS directly from the Internet (no need to key DInstalling or disk, if your Mac date after 2011 it can start with Wi-Fi or Ethernet, however Me it put me on the original OS, ie Lion. So suddenly I had to update thereafter, it takes quite some time, even if I have the fiber). And using my SIN as TimeCapsule, I could find my Mac as before: even to the point to have the same open windows with their stored position (impressive).
In short, a tip: do not hesitate to move to SSD if you still have an HDD!