If you want to talk about imagined (or unreal) situations in the present, then "were" is the correct form of the verb.
However, it's becoming common to use the simple past "was". Even though it's not traditionally correct, it still fits the rule of using the past form of the verb in 2nd conditional (=imagined present) sentences.
I still use "if I were...", "if it were..." and so on. That rule is still valid. "If I was you, I'd...." still sounds like a mistake, though.