https://www.amazon.com/Pedros-142722.../dp/B001Q270CC expensive but worth it.

On tough ones, I have two 30" pipes; one that I slip over handle of the vise whip and the other over the wrench on the lock ring tool. With that kind of leverage, it is easy.

I purchased the vise whip after I could not get a Suntour cassette off a wheel, and my favorite bike shop broke two chain whips trying....

I haven't tried an impact wrench on the lock ring, I suspect that it would work well also.