It's good to know I'm not the only one!
If I start in Painter, I do tend to have both Painter and PS running (which my processor loves) at the same time, though they don't have a perfect compatability, especially when it comes to layers and layer groups. Textures and effects applied in PS need to be flattened to layers below before even attempting to rework in Painter or they just go wacky.
They say some of that is solved in Painter 11, but I can't quite justify the cost for the benefit yet...
I guess you just use whatever works at the moment you need it and hope to learn more along the way!