I bought this rose almost 20 years ago at a small market with a seasonal garden center. The rose was not branded; the packaging and tag identified it as a shrub rose, variety “Bonica” but after a couple seasons, I concluded it probably had been mislabeled. Neither the growth habit nor the blooms look like those of Bonica specimens I’ve seen at nurseries and in photos. Rather than growing into a compact spreading shrub (as Bonica is described), this rose was a sprawling, rampant grower that developed 6- to 10-foot arching canes and long lax laterals, eventually covering a tall fence. The overall growth habit suggests not so much a floribunda (Bonica) but rather a wichurana rambler/climber hybrid (e.g. New Dawn, which I also grow).
Blooms on my “mystery rose” are double, averaging about 3” across, in a clear, strong pink (not the shell pink of Bonica or New Dawn), fading to a softer, paler pink as they age. Fully open blooms show bright yellow stamens at center. The petals look somewhat ruffled at the edges.

Fragrance is slight to nonexistent. Buds appear in big clusters, sometimes as many as 12-15 on a stem.

They don't all open at once, so blooms of varying colors/ages often appear in the same cluster.
Heaviest bloom is in late spring/early summer, spanning a month or so;
repeat bloom occurs throughout summer but not as heavy as the first
flush. This rose has made it through Michigan winters (Grand Rapids/zone
5) without protection. Hips will form if blooms are not dead-headed.

Foliage is shiny (but not as dark and glossy as New Dawn’s ), medium
green, with red-tinged edges on emerging leaves; leaves are arranged
five to a stem except for terminal leaves, which are three to a stem.

Prickles are large, plentiful, unforgiving, and look a great deal like those of New Dawn: angled slightly downward from the stem when young, developing a slight curve as they age.

Here's how my "mystery" rose looked at its peak, in 2009 (this photo does not represent bloom color with complete accuracy):

Sadly, after several hard seasons with multiple problems, the bush is now struggling (another issue for another forum) but anyway, here's how it looks right now:

I'm hoping this rose will be able to regain its vitality - but for the moment, I will just be really happy if some seasoned rose growers on this forum can help me definitively identify this rose. Thank you so much!