I fail to see how the 2nd to last item is rushing to it. The Infinity Edge is what we're going for first.

starting with the vampiric scepter will make her squishier early game due to the fact she will have only around 400-475 hp. tried it bro, sorry, this is a little too far fetched seeing as how you are rushing a bloodthirster. BF Sword is too expensive early game and you dont have enough capability to survive long enough to obtain the sword without losing a tower so early. try again dude... i will try to help you if you need anything.
Sincerely, Blakhart

While running fast is a good way of avoiding stuns. More than likely you will be stunned at some point and when it happens those few seconds shaved from tenacity will save you a lot more imo. But thanks for the feedback :D

This is a pure ownage Build. Safe Mid gaming at begin and after buying VG sword bestial ganking. But i think that Swiftness Boots are better for her, then you got a Team with easy avoidable Stuns.

Greetings.

I like the item sequence, but two things. One is that the dorans blade gives a decent early ad boost that allows you to get early kills. Also i feel sheen is almost a must for vayne. The 100% extra damage is huge on her roll which procs it. I basically use those two before the build you have. So not bad overall.