All the shops I've been in use rough or hit and miss depending on species, availability, timing, usually get one edge ripped on the hit and missed too presently. Hard to make doors flat using s3s, I suppose it would work for many FF's and fillers, but everything seems to go better when the process starts with flat square parts. Stock prep isn't that high of a total % of labor on a given job, so its chasing marginal stuff. Just ripping parts to width from prepped lumber can lead to bows and warping, seems better to do that while stock is still a bit fat? I worked at a place where we flattened and milled stuff for other shops occasionally, it was always interesting to talk to guys who were used to using "flatish" S3S after they used actual flat square parts. invariably it was "Wow, stuff goes together easier when we start with your stuff." I guess its what your used to?
"A good miter set up is like yoga pants: it makes everyone's butts look good." Prashun Patel