Sorry, I don't check this forum often. Are you looking for a brand recommendation or just info in general? I don't have one but my neighbor (also trying dwarf trees) & a good friend both do. I can ask around for you. What size are you looking for? I will mention that I had one in a previous home and battled aphids. Not sure if it was from the previous owner who had quite a bit in the greenhouse or something I brought home from the nursery. Just be vigilant. We also look after our neighbor's greenhouse when they are out of town. I do know they keep a small heater in case the weather gets really cold/freezing. We're just outside Huntsville if that helps.

How large are the pots and what is their construction? Generally, plants in pots in a zone 7B are just fine over winter, especially very cold hardy plants like roses. The ground soil never freezes to any significant degree and if the pots are adequately sized (2-5G or larger) it is highly unlikely they will freeze either. The primary concern would be with quite small containers (like 1G's) or with terra cotta, which itself is not very winter hardy and can crack and spall.

My brother has a rooftop terrace adjacent to his work condo in the Pioneer Square area of Seattle and grows a variety of containerized plants there, including azaleas and has for 20 some years. Azaleas are quite hardy and can take the PNW weather quite easily, even in containers. His only issue is this is a south facing terrace with unrelenting sunlight and so he pays very close attention to watering needs in summer.

As a rose addict who tries to cram them everywhere, I will have to agree with towandaaz that they really prefer sun and may not be the best choice for your situation. From Christopher's list, I do have Marie Pavie, Clotilde Soupert, Sweet Pea and Lindee in partial shade areas. Lindee & Sweet Pea are in the ground, but small enough for a pot. MP & CS are in very large pots. Lindee gets more sun than the others, and flowers well with clusters of small blooms. MP, CS & Sweet Pea have great spring & fall flushes when the trees aren’t fully clothed in leaves, but bloom much more sparingly during summer months with the trees allowing little direct sun. MP & CS have small, but highly fragrant blooms. Sweet Pea doesn’t really WOW me, even when in full bloom. If you really have your heart set on growing a potted rose in mostly shade, my suggestion would be Gruss an Aachen. I have two that bloom well considering they only get a couple of hours of morning sun during the summer months. Mine are in the ground, but are small enough to be happy pot grown. They have large, full blooms with a light, but sweet scent and ever changing colors. I have also grown the original Knockout rose in mostly shade with decent bloom production (tried a Sunny Knockout in shade, but it didn’t flower well there and have not grown any of the other Knockouts). Lindee Sweat Pea Marie Pavie Clotilde Soupert Gruss an Aachen