I did it right when I opened my new 2017 MacBook Pro (15-inch TB) as it was preinstalled with Sierra.
So far I have no complaints, however admittedly I can't compare it to Sierra as I didn't really use it with Sierra. That said, I am getting excellent battery life and performance, both for the most part as advertised.
I use Final Cut Pro, Logic Pro X, Photoshop, Lightroom, iMovie, Dreamweaver, After Effects, and many more graphics intensive applications and processes and I have literally zero complaints with performance on my MBP and High Sierra.
I know I didn't directly answer your question as I can't compare it to Sierra on the 2017 MBP, but with High Sierra my performance with the above applications that are graphics hungry has been fantastic on my 15-inch 2017 MacBook Pro.
Cheers