Somewhat OT but I'm surprised the woods in a zone 9 part of SW UK are so bare looking. Have no broad leaved evergreens started to naturalize besides Rhododendron ponticum? (the ivy is native)

Parts of say, Sonoma county would look like this perhaps, though I noticed that even there the copses of deciduous trees are often covered with that peculiar lichen that resembles spanish moss.
I guess it's just surprising to me that places that can grow many plants native to Tasmania and New Zealand haven't started to look more like them. Not that that would be a good thing, necessarily, from an environemental POV.

I have a small formosana that I will eventually plant out once it attains some size. Already have macrolepis in the ground and it is doing quite well. Eventually would love to get my hands on rupestris, which is really cool looking.

"Somewhat OT but I'm surprised the woods in a zone 9 part of SW UK are so bare looking"

Looks to me to be quite a young plantation, no doubt any evergreen species haven't had tome to colonise yet. European Holly Ilex aquifolium is the local native evergreen broadleaf tree.

Resin

I have a small formosana here doing great.

"Eventually would love to get my hands on rupestris, which is really cool looking."

For my taste rupestris I agree is very cool looking as a young plant, quite similar to a succulent. It also reminds me a lot of a young tapeworm plant Homalocladium platycladium. But as it grows to me it loses its charm somehow, I don't know, the big ones don't have the same appeal. Only a personal opinion. Now once they come up with a permanent juvenile-looking dwarf cultivar it'll be a different story...

How big are the biggest ones (rupestris) you have seen? I have seen some in the 10' tall range. They are very narrow and dense - almost columnar. I suspect in cultivation they may look different from what they look like in the wild (though I have only seen photos of these).

Here is a close-up of the foliage of my formosana. This clone originated with the Pinetum Blijdenstein, I believe.

Yes Jason, I have seen them at a similar height, they look like a tree trimmer took a serious go at them, very dense and columnar. I have seen photos of wild trees and the foliage looks much more open, the crown and branches are loose and not hugging the trunk. Young sprawling plants with their segmented green branches are a show-stopper, that's the stage that really appeals to me. Do you think the older cultivated trees are as attractive? It's only been a few years so maybe they improve with age.

I like the columnar form, but it is definitely the foliage that makes this species so attractive. So, young plants will be best. I guess time will tell how they look in cultivation when older.