only thing i don't care for in those bearing kits, is they don't come with the spacers and dust caps for the a arms and swingarm pivot. if your spacers are worn out or trashed its easier to buy a pivot works a arm or swingarm rebuild kit which includes everything new.
also your not getting the linkage or shock bearings either. other than that there good. i've used boss axle and wheel bearings before.
i've used those ball joints, there on my 500, also on my 250. the boots on my 250 joints are now ripped, so they need to be replaced. when i replace them again i'll buy oem. they cost alot more, but also last alot longer. got over 10 years out of new oem lowers on my zilla. these chinease ones don't last, well haven't for me. but there cheap enough to replace.