You have been randomly selected to participate in the Beta Test of our new message list page. We've rolled out this test in order to get additional feedback and error reports from a wider subset of users. We'll only display this notice once, but permanent links to disable the Beta, provide feedback, and get more information will be located at the bottom of each message list.
Most low rank and some high rank armor sets do not have high enough skill points included in each part to allow for mixing. Once you reach Grank the armor set parts will have sufficiently more skill points.