Hi guys, itīs me again with a question.

I recently decided to go for a new 8k stone.
I went for a Shapton Glasstone at Dick.biz in germany (yes, the company is called "dick").
It is the only vendor I know that carries any Shapton GS in germany (even europe?).
I was kind of excited when I saw the stone arriving today was grey, not white as I expected.
The label says 50803 wich indicates the new shapton high carbon (or high polish) 8K stone.
Interesting, I thought they carried the usual white ones...

The stone itself is quite nice, has a good feedback and gives a nice edge slightly finer than Naniwa Superstone 8k
and a tiny tad less keen than Naniwa Super 10k.
The edge compares to my green coticule.

But I find this stone to be a bit slow cutting. Significantly slower than Super 8k and comparable or slower than Super 10k.
It removes teeth from the edge but will not remove scratches left from my mid section stones like Chosera 5k, Shapton Pro 2k, Cerax 6k or Coticule with slurry.
If the edge is polished by a stronger 8k stone, the GS HC 8k will improve it and refine/keep the deep 3D mirror polish that I love so much.

So I guess I will need a new ~6k stone that will leave less deep scratches that the HC8k will be able to remove better.

Would the GS HC 4k do the job?

Does the 4k leave a finish that will enable the 8k to show its potential?
That is, is the HC 8k able to remove the HC 4k scratches completely?
And is the 4k fast enough to be used after common bevel setters like Chosera 1k or DMT 1.2k, or is it too slow?

Should I go GS HC 4k -> HC 8k
or would the HC 6k be of need?