Rolls Razor hone

Recently, I thought I'd give the stone from my Rolls Razor a try on my str8s. It seemed to restore the edge pretty well. The blades in question were not dull, but they had some trouble with the hanging hair test. A few laps on the stone (I popped it out of the metal case) and then a stroping seemed to pretty well put the edge back on the razors.

Anyone else try these stones? The Rolls Razors come up often enough on ebay and rarely sell for more than $20 (I imagine)They might be worth it just for the stone.