If you have purchased the 2016 version, I don't think this refresh would be worth the upgrade. The entry level non touch bar saw a nice bump in processor speed but ultimately nothing to stress over. The 15" also got the mid range 455 graphics so that's a small bump from the 450 (entry).
Overall, nice improvements but nothing drastic as expected.
Its not even an option. I'm one of those people that need RAM. Lots of RAM. Its not my fault, but the OSs in the VMs I need to spin up want more RAM every year, and Apple's limits haven't budged since 2011. It is to the point I have to travel with a 2nd machine, because 16GB just doesn't cut it for my workflow. And 16GB is all they will sell me, so no upgrades in the foreseeable future.