Wow Hellonasty, that's certainly pumped it up ! Looks totally different... thanks for showing us it...
Kanje, they're not what I'd call very slow, but they can be quite touchy on their own roots and the seed can be hard to germinate. I have plants on their own roots that are about 4 years old that are budding up, so probably the same speed as a lot of other stuff...
Knowltonii is probably the "easiest" and one of the best of the Pedio's though, should you ever want to give it a go...