Some prefer it to the bush version.

Wow, that's one nice plant! The climbing version at the San Jose Heritage Rose Garden has never looked great when I've seen it (lots of PM and a generally sparse, ugly foliage), but that certainly isn't the case with that nursery's plant! Because of how the SJHRG plant looked, I hesitated for many years to put SdlM in my own garden, but the bush form I eventually planted does fine here -- shakes off the bit of PM it might get in early spring and is altogether lovely. I'm thinking the SRHRG climbing SdlM may just be in poor spot, for whatever reason.

I grew the climbing form in a previous garden in Sydney decades ago. It clambered up a flowering plum bang next to the house, on the east side, and did very well. No disease and flowered a lot. Had the bush form in my present garden for a while but it wasn't happy here.

What a gorgeous rose Adam, congratulations!

I had this notion for the longest time that bourbons were a particularly unhealthy class of rose, but posts like yours showing flawless foliage on climbing SdLM are making me question that. Do you have to spray to get her to look like that?

Titian10b, how was the leaf health on the shrub version?

Sadly it isn’t mine, it is growing on the verge against a chain-link fence out the front of a nursery in a light industrial estate; fully exposed to the baking western sun and strong southwesterly winds.

I doubt any of those roses are sprayed for pests either.