I do bring in the PSD for visual reference when I rebuild the comp, but it's not much more useful than that. The PS layers import as document size (i don't see any "import as layer size" option), which makes picking the layers pretty much impossible, and the anchor point is never in the right spot if i'm going to do any scaling or rotation. Also, sometimes I need to break layers down into smaller object subsets and I can't do "convert vector to shape layers" with PSD layers.