Chris
#2 is a great shot. Shows what can be done even with Sigma glass

Local word is that the observation tower in the photo is going to be demolished by the council for some reason. Did you go to the top - the view is great.
Mudder
I agree with you about the barrel distortion not being evident. Some would say (Chris, Glen) that's because it's the Sigma 12-24. I have the Nikon, just in case this isn't obvious

and I find it takes similarly low to no distortion shots. Both are nice pieces of glass (obviously the Nikon is better

)