Originally Posted by Guy on a bus
Correction: Add rush BT to the 'don't' list. Add Rush PD to the 'do' list.
You want damage and survivability before you want movespeed/crit/aspd.
Sorry, but you're wrong. Never rush PD, ever.
That said, Infinity Edge is slightly superior to Blood Thirster unless you
a. Can farm like a boss right after you buy it.
b. Can stay alive to keep stacks on it.
After it gets fully stacked it provides more than Infinity Edge, but Infinity Edge is stronger right when you buy it. IE also synergizes better with PD.
Also, Trinity force is NOT a bad item on a select few ADC's... Namely Ezreal, Corki, and sometimes Sivir.