Currently own a 2016 13" nTB 8/512, which I will be changing out for a 2018 15" base i7/16/512/555X in the next month or two. The nTB has served me well, but I'm looking for just a bit more oomph and some more screen real estate, which is why I'm looking at the 15".
I’m in the same boat. 2016 13” nTB base model. Very tempting to try 2018 15”.