Top should be:
3600 15-15-15-35 1.35V
4266 16-19-19-39 1.45V
4400 16-19-19-39 1.50V
To quote myself and add top bins for dual rank, first 3 should also be the tightest:
4000 16-16-16-36 1.40V
4000 16-19-19-39 1.40V
4266 16-19-19-39 1.50V
4400 17-18-18-38 1.50V
Probably also very good is 4000 14-15-15-35 1.55V, but I wouldn't bother with it for Intel unless I found a review where it is clear how good it OCs.
How I know these should be the best/tightest? I got 4000 16-16-16-36 and it errors right away even on 1.39V, but 1.40V is stable for 24 hours. And that's on 54°C.
It also does the other 2 CL16 XMPs on exactly the same voltage. Last one is only good if you run XMP, otherwise it is not top bin as my 4000 CL16 needs only 1.47V and 3600 CL14 needed 1.51V.
I still don't know what's the point in 4000 16-16 kit if they already had the 16-19. Everyone thought it is worse than 3600 14-15, but for CL16 OC it should certainly be better, most probably also for CL17.
And 4000 20-16-16-40 needs around 1.35V anyway on B-Die, so 16-16 might be better bin than 16-19 or it might be exactly the same.
My 4000 16-16-16-36 doesn't work 4533 which is disappointing as 3600 14-15-15-35 was stable on 18-18-18. Here not even 20-22-22 works. But I wouldn't run my IMC on 1.40/1.25V anyway, so it makes no difference.
Plus by my testing 4400 17-17-17 is a little better than 4533 18-18-18 in AIDA64 write and latency, and 4533 C18 is a little better in read and copy, so they are all the same.
Anyway, I've had it now for DDR4, I have other things to do besides RAM.