Thanks seems like it may be worth the upgrade! Many thanks!
You're very welcome! Please bear in mind that neither the 640 or 650 are gaming GPU's. I have a dedicated gaming laptop for heavy duty stuff. However, I was still surprised that my sleek MBP 13 2016 (with a 550) could handle games like "Deux EX - Human Revolution" and "Doom 2016" at 720p with medium settings and have on average 35+ fps. Even "Just Cause 3" was doing ok. Of course, I'm using Bootcamp with latest drivers and clean install (no much processes or icons running in the background). All in all in "high performance" mode (both Intel control panel and Windows one). Basically, all optimized. Even the latest Prey, in medium settings and 1280x800 is giving me 40+ fps on average. We're talking about a 550 on the 2016 model. As per experts, the 2017 one, with a 650, might give you about 15 % performance increase.
Last year, I was testing a Surface Pro 4 with an intel HD 540. When the game starts and there's no action, fps were similar to the 550. However, as soon as action comes in, the fps on the 540 dropped substantially, almost like a slideshow, while the 550 usually remains more stable, with some lighter dips. Again, those chips are not meant for gaming. But sometimes, you just want to bring one nice laptop (the MacBook Pro) and make a few compromises, performance wise...