Finished watching season 4 today. I think I started about 1½ month ago with Season 1. I love the series. One of (if not the) best drama series I've seen.
I loved all seasons, though I had sometimes had the feeling there wasn't a real build up towards a climax. It just feels like one big story split in 4 different seasons. I think Gus was a great villain. The two-face VFX were pretty good.
The first two episodes of season 2 are my favorites I think (where Walt and Jessie get abducted by the Mexican dude). So intense. It really felt like those 2 episodes where supposed to be in season 1...
Great cast, especially Bryan Cranston is a great actor. I love how Walt starts as a 'father on auto-pilot' and is pretty bad ass later on.
The only think I found really really lame was the airplane crash. It felt so incredible stupid and out of place. I also found the two Mexican cousins pretty meh.
Anyways bring on season 5! Can't wait.