Just got a 2k stone today and gave it a whirl and wanted to post my thoughts.
i was really amazed by how fast this stone cut, i was thinking ok ya it cuts fast but i wasnt thinking it would be that fast.
I used two victorinox chefs knives one on the G2k and one on my minosharp 1k. I was able to raise and remove a burr on the 2k within 3-4 minutes ready for the next stone. It too about 7-8 minutes on the 1k using same pressure and technique. ( keep in mind in no expert or expert sharpener)
Also i would never be able to use the edge off the 1k in the kitchen just not enough refinement its sharp but feels forced through objects which i hate and always feel i will cut myself.
On the other hand i felt comfortable with using the edge off the 2k its sharp and toothy but enough refinement it went through onions with no problem.
For me though i like an edge that just falls through no frills so i took it up to a 6k stone.
I wished i would have gotten this stone sooner this is my second gesshin stone and i plan on getting the 4k and possibly 6k soon they really are great.
I have not had experience with other "high end" stones however i dont think after using these i could be any more happy.