No I dont think thats a good idea  X Magenta is completely different from the meaning of magenta for centuries before  I think the X guys needed a name for FFFF and just picked magenta as the first thing they could think of  I agree its good to have a source but the X colors arent a very good source for this IMO  We could try converting  magenta ink color maybe like from some SWOP CMYK space to sRGB using ColorSync or some other CMM and then source that as the color for Magenta  But really this is a reason that I dont like swatches for such articles Magenta doesnt refer to a particular color so much as a range of colors