User blog comment:Mineko Charat Lucky/Stop Telling Me What to Build, Thanks/@comment-18521310-20131013055043/@comment-1330314-20131014125053

You can buy six, but the magic penetration won't stack (and neither will the movespeed). You can, however, buy six different boots, get Tier 3 enchantments on all of them, and benefit from their highest movement speed bonus, along with every stat boost and enchantment bonus.