According to Treloars, chico2, one of the leading rose suppliers here ....
(quote) All roses require an open, sunny and well drained position. AT LEAST 5 HOURS OF DIRECT SUN PER DAY IS REQUIRED(their emphasis, not mine, it was in capitals in the cultural notes), preferably more. Although shaded areas will allow roses to do well, the quantity of flowers will diminish with the percentage of shade. (end quote)
So, it may be that because mine is in full sun, the colour is more vibrant. I love the slightly muted colour of Shirley's though, and it has such a lovely form, that rose. Looks fantastic in her photo with so many blooms.
Just Joey is an unusual rose, it really alters dramatically when exposed to cold weather. Grown down in Tasmania where it's cold, it can be like this
or grown here in Victoria when it's warmer it can be like this. Without frilling on the petals and it's the 'coppery orange to buff ' colour that it should be. You'd think it was a different rose.