Great, now here is the counter example,My 330mate Ohiro Suita works fine as a finisher. It isn't as fine as my Karasu from MMJP, but it's finer than my Karasu rubbing stone from Maxim and my Konyama Razor Hone from Dicks, and almost as fine as my Asagi Tomo Nagura from Chef Knives To Go (I think that's where I got it). That's just grit though. The shape is odd (about 5x5 or so... The part I USE is like 4x3"), and it needed lapping when I got it, but it is almost as easy to use as my Konyama Razor Hone (which is damned easy to use).
Of course this isn't a Random stone. It was sold individually, rated at 5++++ grit, and noted as an excellent stone for final finish on Razors. It was also quite affordable thanks to it being such a weird size and shape.
I still prefer my MMJP Stone, because it is finer (pretty ridiculously fine in actuality), but the 330mate suita is still a nice finisher.
Now my RANDOM stone ($25 "Razor Size" 330mate eBay listing), isn't a great finisher. It's a bit too coarse. It's a very very fast mid-range hone. If you're spending $25 and expecting a great Razor finishing Jnat shipped from Japan (meaning the seller is probably getting ~$10 for the stone), then I want to live in such a world. It gets used occasionally, but I actually prefer coticules for that range of honing, so it's mostly retired.
I too got a 5++++ stone that was not one of the random e-bay stones and was also listed as a razor hone but it is nothing more than a prepolisher. Mr. Nakaoka does not test the stones on razors to be sure they are good finishers, so it is very much a hit and miss no matter what he tells you.