I have had three mini RSKs - Two made by Benchmade (S30V and M390) and one made by Hogue (20CV). Functionally, I could tell no difference between them as far as action is concerned. The S30V from Benchmade is much thinner behind the edge, while the M390 from Benchmade and the Hogue are very similar to each other in that regard, and thicker behind the edge. I liked the feel of the Hogue handle better. However, as financial pressures led me to sell some of my collection, I sold the Hogue. My biggest beef with the design is the open back. I know a lot of people like it because it makes the knife easier to clean, but for me it is an irritation because if anything else is in the pocket with the knife (which is usually the case for me), invariably the edge gets blunted as things find their way into the open back.
When Hogue started producing the RSK, there was a question whether the basic design was (or should be) licensed with credit and royalties to Mel Pardue. I don't recall if that question was ever fully resolved. Perhaps someone can answer that definitively.