IIRC the RAT2 uses AUS8 blade steel, which is generally easier to sharpen than 154CM. S30V has higher wear resistance than 154CM and it is generally more difficult to sharpen, with some users reporting it is significantly more difficult to sharpen.
What are you using to sharpen? This plays a huge role here, especially with higher performance steels. Further, what angle are you sharpening the Benchmade at, and what grit stones are you using?
I think we can get you to a point where you are getting the 154CM as sharp or sharper than the AUS8. 154CM is a fantastic steel, but a little more tricky than some others. A product like the Spyderco SharpMaker is one of the finest in existence, can sharpen anything made of metal, is very affordable, and is super easy to get any and all steels super sharp. And an inexpensive strop can help you periodically revive the edge so you have a razor sharp knife 24-7 and you reach a degree of sharpness that exceeds that of what you got from the factory.