Ghostblade Ashe

I have been playing around with a Ashe build i am liking, but i need some advice on how viable it is or could be.

you start with

then rush into then build then

The GB active + Q + Runnan's produces a surprising amount of burst on the target that ashe has applied her passive on. in addition to this you get a burst of movement speed that along with ghost or cleanse deals somewhat with a weakness of Ashe.

After IE is another problem my initial gut reaction was to go with for 40 arm pen and 2 shields.

But if you see 2 or more tanks out in your game maby amd new Trinity Force would be better