A few months on, and I am very pleased with this power supply. I use it in all my Nixie clock projects. The version I use all the time is the one with the WE-FLEX transformer. As it seems to be necessary these days to show that it can drive a bunch of IN-18 tubes from a single LiPo, here is my power supply doing just that:

I also made a version that produces 240V out, so I could drive IN-28 tubes. To do this I just changed the resistor values in the feedback network. So R2 became 8.66K instead of 10.2K and R3 became 24.9K instead of 33K. That is one of the benefits of knowing your power-supply inside-out: You can easily modify it to suit your own purposes. Or fix it if your transformer goes up in smoke, like that one did when I over-drove it. Now it has a larger current-limiting resistor too.