Completely different question but how about comparing last years spec'd out 15" vs todays spec'd out 15"?
So a 2018 2.9 i9 6-core, 32GB RAM, 1TB, Vega 20 versus a 2019 2.4 i9 8-core, 32GB RAM, 1TB, Vega 20.
If someone had last years is there much of a difference in those extra cores?