I still have the OEM shocks on my Custom and is 12", so probably the same stroke. You have to figure about 1/2" for the sag, so the effective stroke is even less. I'm not a young whipper-snapper any longer but it's tolerable for me at 160lbs.

I also ride a Road King and I have 12" Ohlins rear shocks on it. The shocks have a 3 1/4" stroke, and am looking into replacing the Sporty shocks. Those shocks are as smooth as butah...well maybe margarine.

 

The combination analogue tachometer / digital speedo is also available for the 2014 and up as well, it is a nice upgrade. I have one on my bike complete with the fuel level sender so I have a fuel gauge and range to empty which is pretty good.

The 2014 also has a keyless ignition option. For international models that is all they shipped.

 

Unless your super picky, the 2013 is a great machine. Like others have said, I think the biggest difference is the newer CAN bus electronics.
I've had my 2013 almost 6 yrs now and its super reliable and super easy to maintain.

 

As I recall, there were a bunch of changes in 2014. Mostly small things, but a big one to improve suspension. Doesn't mean it's a great little bike as is, though. I'm in the process of buying a 2012 XL1200CP for example.