Just onto season 5 now of the re-watch, and Walt is the biggest pathological liar in the history of TV shows. I actually can't stand him, but what a piece of tv writing that i've literally gotten two different experiences watching the whole thing through twice. Not sure if it was layered that way intentionally but its genius. Some of the opening scenes that appeared so random and weird the first time are brilliant, like the Guy at madrigal tasting the sauces and then killing himself with the AED machine. The episode and the show didn't need it, but they included it and it worked beautifully.
The one thing that sticks out is that Gus was inconsistent with the security measures he would take. He obviously isn't the type of guy to need security with him when in public, but a couple of times he has his goons walk him to his car including from the hospital.