Changed the Spark Plugs - How do the old ones look?

So I've owned my 04 6spd since Jan 2013. I bought it with a little over 81,000 miles on it. As of today, it has 99,319 miles on it. I'm the 4th owner, and I have no clue what the service history was on the car. Overall, the car was in great condition when I bought it. The dealer that I bought it from installed a new clutch, PP, and flywheel.

So having said that, I decided post hurricane weather was nice so I would knock out the plugs. Read up on a DIY and it was pretty straight forward.

Below you will find pictures of the old plugs. The order of the plugs, is the order in which they where if you looking at the engine from the front of the car and the hood open.

I don't know how many miles where on these plugs. Its my DD, it regularly gets 23-25 mpg around the city, and usually 29-30 mpg on highway driving.

Thoughts?



Plug # 1:



Plug # 2:



Plug # 3:



Plug # 4:



Plug # 5:



Plug # 6:



Thanks!