Sorry, I currently have a 2018 TB MBP the 512GB one. Before this, I had a 2017 nTB base model
Gotcha. I missed that, I saw the part about the 2017 base model. I take it you have the 15" 512GB one and not the 13" 2.3GHz with 512GB? IF the 13", it wouldn't be as much a step back going from that to the 1.9GHz SB6. But the Surface Pro 6 is probably more of a competitor to the Air performance wise