MacBook Pro Mid 2014 VS MacBook Pro Late 2016

More Ram is important.

But the speed of the SSD is much faster in the late 2016 mbp.

Also look at the connectors, different.

Then you might find the TouchBar interesting (I don't), and the Force Touch Trackpad in the 2016 model.

But also I would look at the Battery Status: In Applications->Utilities->SystemInformation select "power" on the left side, then read the "Battery Health Information at the right side: condition and cycle count.

93 cycle count and health "normal" is a young battery, good. Get worried when it is closer to 1000.

Depending on the apps you use, CPU speed is not really important: important is the number of cores. I am not sure but I guess the number of cores is the same in both macs.

Depending on your applications, important also is the graphics and the memory in the graphics card: in the 2014 mac sits an Iris graphics card without specific memory: used is main memory, so it is good that it has 16gb of Ram. The 2016 model has the same: no memory for the graphics, also using the main Ram.

The difference of the SSD speed will not be so much that you will really notice.

Maybe you can negotiate the 2014 price a bit lower.

One big difference between the two not mentioned yet are the ports and power adaptor. The 2014 model has USB 3 ports while the 2016 model has USB C. The 2014 model has 2 Thunderbolt ports and an HDMI port as well as MagSafe. The 2016 model has 3 USB C ports (Thunderbolt) for all I/O and electric.

For me, the 2014 model, while it may be marginally slower, is the winner because I don't wish to beta test an all USB C machine and the requisite docks, cables, and dongles.

The one with the faster processor and more RAM.