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I have used the Shapton GS 30K for a while, and the Shapton Pro 30K even more.
While great hones, they are both quite finicky when it comes to what razors actually benefits from a trip on them.
As...

Condistency and speed.
A good JNat will deliver on par with it, no worries, but for sheer condistency and speed, the Gokumyo is, IMHO, the king of synth finishers right now

The Chosera 10K-Gokumyo 20K is my preferred final progression.
Try it, I'm sure you will find it to work well:)
Good luck

Agreed
That 20k is brilliant in that, actually cutting while polishing to a sublime level