Really poor item choice. Should build Skirmisher's Saber, although Stalker's is nice due to mov speed steal, Ninja Tabi are close to the worst boots in the game for Vi, boots of swiftness plus the Tenacity masteries would completely negate your Q slow, so ganks would be 200% better, almost viable to use Ghost (Due to smaller cooldown than flash), Trinity Force passive doesn't stack with Gauntlet, by this I mean: The trinity force damage will still be there, but only the slow from Gauntlet will proc, big waste of money, deadman's plate much better, Guardian Angel is good when you're fed, and apart from the fact this is a Tank build, that revive is useless, really only because once you're alive again all your team is dead, supposedly. Masteries are fine, but I'd rather not take Vampirism and Fearless. Vampirism won't do anything for you, especially when you're tank, while natural talent isn't much better, it will give you some nice AD for late game to proc with W. Fearless is a good talent but there's one issue, it's 2 seconds of massive resistance boosts, your ult takes more time than that to reach the enemy in teamfights, I'd take Insight over it, but honestly, that one is up to your personal preference. At last the big mistake on these masteries are the Veteran's Scar, it should be Runic armor, ALWAYS, since both Vi's passive and the Keystone mastery you chose will benefit of that. TL;DR: Vampirism is good, with all things accounted, 10 hp per hit, it's really good, but in all honesty, late game it does you nothing with this build. I hope I helped you understand some things.