I've tried to play it, but the game is more demanding on the computer than many other games of the genre, even at minimum settings.
* On my desktop with cooling issues, I get smooth motion at first, but then the computer overheats and throttles, resulting in lag that makes the game unplayable.
* On my laptop with a Celeron CPU, the game is playable, though not exactly smooth. Unfortunately, it's not as comfortable to play on a laptop because it's too big to be comfortable as a hand-held and too small to play it like a console or desktop.
As a result of this, I have not yet been able to fully enjoy the game, but I have at least enjoyed the soundtrack, which is definitely worth it.
From what little I have played of Hollow Knight, my main issue is the way saving and death is handled; the game only has auto-saves, and when you die, the game punishes you for it and saves the punishment.
(Note that this desktop can run games like Timespinner and Celeste without issue.)
KiNgBrAdLeY7: VERY!!! But beware, it is absolutely mandatory for you to GIT GUD! Or else, various hazards may happen, like you breaking your screen, smashing your keyboard, hurling and throwing your mouse away, etc. Or bashing the controller against the wall. You need reflexes and precision, on that one.
I myself was urged and motivated to upgrade my platforming capabilities, with this gem. But when i reached impossible challenges (Nightmare King, white palace secret passage, final colosseum level and almost the entirety of the final DLC content (god-something), i was forced to use the INVULNERABILITY MOD. I merely wanted to 100% the game and collect all entries, or else by myself, i did a damn fine job, with 106% beaten legit, out of the 112.
Get it. Worth every penny. I got through special discount in mail, for 6-7 bucks. Mighty example of how kickstarter stretch-goals should be handled, too. Devs implemented even the first one of those who didn't make it to be funded and the secondary player, turned into an entire game, in and by iteself, instead of a small content addition!
Have you tried any of the dedicated precision platformers, like Super Meat Boy or Celeste? Playing those games will definitely help you with your platforming skills. (I could also note that Celese even has an invunerability mod built in.)
Then again, I figure that Hollow Knight and Celeste aren't games you're interested for the reason that you rejected my suggestion of Timespinner.