I really could care less what system we use, as long as you can tell me a particular color name/number, that both you and I can reference in our own charts at our own locations.
*also as long as it has more values than CMYK, designing and providing colors in only cmyk is plain ignorance on the designer's behalf.
Oh, and update to the story, we mixed sample paint, and printed sample swatches based on those two sets of cmyk values and the pms values out of corel, customer didn't like anything, wants to see other colors...