I went from PaintTool SAI to Clip Studio, and I HATED Clip Studio at first.
I thought it was a waste of my money. The brushes were not doing what I wanted, the pen pressure seemed wonky, there was too much going on in the UI, etc....
It took months of using it on and off before finally something clicked with me and I started "getting it."
I now use CSP for all my comic work.
I still use SAI for my illustrations, because I have a brush setting in SAI that I really like and haven't found any equivalent for CSP.