Josh rebladed this rock-solid, Hall of Fame Rukus 610 for me a while back, and it's been my EDC ever since. The steel is Vanax SuperClean, probably the best balanced knife steel. It's used only in custom or high-end production knives today (called Vanax 37 in Shirogorov knives). Super fine grained, so it easily takes and holds a fine edge. It's the toughest of the stainless powder steels. It's almost completely stainless -- maybe H1 is better, but it's close. It replaces the stock 4.25-inch S30V steel blade. I've chopped and whacked and sliced and diced and never had a chip or a roll, even with a 30-degree inclusive edge that is just 0.015 inches wide at the shoulders. (The black G10 scales are an optional scale from Benchmade.)
This was an awesome knife with the stock blade. The REK reblade made it epic.