I admit I may be an anomaly but Friesia isn't rust resistant in the foliage for me. I do grow in it a warm and often humid environment though (Sydney, Australia). Very good plant in every other way though.

This rose has been practically indestructible. It was planted in our yard when we bought our house. That year, it was eaten almost to the ground by Japanese beetles. It came back the next, just as strongly.

The summer of our third year, a storm blew a tree onto the bush, breaking a number of canes. I pruned away the damage, but the bush was less than half the size it had been. A strong freeze that winter took out almost everything else that was left, but once things thawed out and the dead wood was taken away, we had more blooms than ever.

Two years later, it's still going strong. The flowers smell wonderful, and the bush is now taller than my mailbox. Yes, the blooms don't last as long as I'd like, but they're plentiful and they just keep coming, so it's not a huge problem.

No issues with blackspot or mildew, even when other bushes are affected.

This rose never stops growing new buds. I planted my first Friesia this year and it already had more than 5 blooms. Right now it has 10 new growing buds. The foliage is really healthy and pest resistant. The scent is rosy fresh, sweet, but with a soapy undertone. The only bad thing about Friesia is that the blooming petals really quickly fall apart.