So I fitted my springs last night after work. Total time, including finding a suitable central (rear) support point (under the diff) was just over an hour - for both sides. I got the springs off easily on my own, but needed someone to push down on the arms to let me push the new springs in, as I don't have a pry bar - takes seconds.
I gave my pads a quick clean up whilst they were off as they were caked in mud and general road grime, then coated the 'ball' of them with vaseline so the spring sat on them properly.