It’s true that converting to mesh is a good option when working with SubD in grasshopper.
However I’ve found that native mesh components won’t quite get me where I want to go. Pufferfish has a few components that are very useful.
This post shows my first attempts to create workflows for modifying SubDs: SubD workflow examples for grasshopper: extrude, loft, offset. Also: Questions about creases
I’m not sure about other people’s progress, but my bottlenecks for working easily with SubDs in grasshopper are creases and face/edge ring selection.