I have been using ACR, I still can't get past the database building of LR, and prefer C1 if not other reasons, just for that. But I notice if you convert ACR to Greyscale, you lose the ability for a plugin when it's greyscale vs RGB. So you have to convert back. Wonder if there is any issues doing this, or if there is a preferred method, as I like using the color saturation and luminosity sliders in ACR before I PS it as I sometimes apply a SilvFX or other plug. Also when using color sliders in ACR with a raw file, I would think the data is used more like Channels tab as it would pull the info from the same source..no? Thoughts?..