I also grew Southern Belle as part of the Hybrid Tea Test Panel. I liked it very much that first year in a container and transplanted it to my garden bed the next Spring. I don't think that this has been as good of a rose in the garden as it was in the pot. The bush is not very vigorous and only gets about 3' tall at the very most. Blooms in flushes with about 7 blooms per flush. They have good fragrance, a pretty decorative form, and are very light yellow and do fade just a bit as they age, but htey never get to the white stage--they are always definitely yellow.
This rose will blackspot with spraying very lightly, so I would not be anxious to see it grown no-spray in an area with higher blackspot pressure than what I have.
All in all this is a pretty rose and if you spray I would recommend it.
However, I think that J&P's "Welcome Home" is a much better yellow HT and I would suggest you try it first if you must get a yellow from J&P.
John

This rose is listed as white blend. NOT. It's a clear yellow when it opens, but fades to a lighter buff yellow within a day or two. Should be "yellow" in the color class, not "white."

I recieved this rose a part of Jackson and Perkins Rose Test Panel. It is by far the best yellow rose I've seen in a long time. beautiful large blooms, wonderful scent. It was constantly blooming. I grew it on my picket fence with my sweet peas, and it didn't mind them climbing through the bush at all.