I love my 3" x 8" ultra fine stone. I usually put a 15 dps edge on my edc knives with my EP.
Super easy to get a tree topping edge back with this uf stone. A little pricey at around $80 but nice equipment.
That larger Ultra-Fine stone of Spyderco's in one of the very few Spyderco sharpening tools I don't currently own unfortunately but it's on my radar screen for sure. Now I've had two of the Ultra-Fine 302 Benchstones for years and they are a great tool for all kinds of finishing. But I can see where a bigger unit would have its advantages for sure. I also want those CBN stones too but just haven't gotten around to getting them yet>> but I will before the year is over.
Again I'm hoping that Spyderco will expand it's GOLDENSTONE and Duckfoot units and do more with them like make them available in more grits. I also seem to remember Spyderco at one time saying that they were working on a base unit of some sort for the GOLDENSTONE>> I sure hope they didn't abort that idea. If they are not going to bring back the 701 Profiles then please make something available in more grits to make up for it. I just know that Spyderco's patrons will much appreciate it.