I had to briefly bugger about with the saddle on the Red bike.
When I first got it, before Christmas, I had a quick fiddle, and thought that the saddle was at the correct height and orientation, but getting it out today, to try things out properly, it was far too low.
A quick fettle with some allen keys, and it's probably OK. It may need to go up slightly, but it works OK as it is, and it's easier to get on and off, which is useful with a new bike which I'm not entirely used to riding yet. I'll probably bump it up another half an inch eventually.
I may need to adjust the gears, but I'll wait a hundred miles or so, to give things a chance to bed in, and for the cables to do any final stretching. The chain jumped off the chainring at one point, and a couple of times the rear gears did one of the change up and immediately change down of their own accord things, which suggests that the cable adjuster needs to be shifted very slightly.