Yes same experience here, it'll perform well for the first 3 keystrokes after a rest, then start lagging, compounding lag to the point where the screen is 5 characters behind of what I am typing, then I have to wait 10-15 seconds for it to rest and report all the errors. It's terrible but there's no alternative for the features.

That's entirely different than having "never" seen it handle keystrokes in a timely manner.

I've seen this too. With recent versions nonetheless.