it seems like you already have the best stones in this grit range. so why buy more of the same? i've had about 10 different 1k stones. and in the end i only kept shappro/glass/nanipro800/hyper. because those were the best ones. i kinda liked the juumas too but i dont like soakers.I have only S&Gs in the med grits: NP800, SP1000, SP2000.
I like all three of them and am not searching to have "better" but "different".
The aim, if not fun of discovering new stones, is stones that are better in a finishing progression, or have other attributes my stones cannot really compete with.
I've been mostly looking at three options, and would likely buy 2 out of 3, or perhaps just one if the feedback seems to indicate it voids the need of any of the other two:
King Deluxe #1200
And let's say the Cerax 700 would help me complete free shipping on a cutting board I'm inclined to purchase - so I'm really inclined to buy that stone too... But I don't care so much in the end, just aiming for the best advice.
maybe you should look into other grits like 3-4-5k or even 8-12k, and then maybe some coarse stones like 200-ish grits?
personally i dont care about the contrast a 1k stone leaves because the finish is simply too coarse and raspy anyway. at 2-3-4k then it starts feeling smooth and nice.