I have three Dalmore Blue stones - all very different. The first is fairly dense, coarse and fast and with a slurry makes a more than competent bevel setter. The second is the more traditional 4k to 6k range. The third is a crazy finisher. Really fine and beautiful edges off it.
There was also a Dalmore yellow which was a coarser plainer stone and was squarely in the bevel setting range. Trying to get my hands on one of those.
The two coarser stones I have work really nicely in conjunction with the other famous Scottish hones - Tam O' Shanter and Water of Ayr. Raising a slurry and diluting with water on each in turn produces an effective progression.
I have found all these Scottish stones really intuitive to use. You can hear and feel when something isn't right with the bevel, and it's pretty clear whether or not you are ready to move on. I like them even more than Welsh stones.
They have transformed my honing. Earlier this year I was having mixed success with synthetics. I still struggle with them. They remove steel so quickly, one slip and I get in a right mess and i just can't read the feedback off them. The Scottish stones hone fast enough that I don't get bored but slow enough that I have time to get my X stokes running consistently.
Decent TOS and WoA sell for silly money right now, but you can pick up a Dalmore quite reasonably.
I am passing the old Moughton quarry this week. I am hoping to get the chance to walk up there and see it.