First things first, it was never a penalty and you don't need multiple replays to see the glaringly obvious.
Secondly, I'm against video replays because they actually solve very little, maybe "was it over the line" goal, or an occasional offside or handball but most controversial decisions will still be controversial decisions whether they were arrived at by video replay or not. All you really do is add another level of controversy - when is video replay deployed? Who has the final decision? etc, etc.