Forest River has several lines that are the exact same trailer, Rockwood and Flagstaff are the ones I am most familiar with.
The primary differences are the interior colors, decals and some minor bits of trim. Sometimes one trailer will have slightly different cabinetry than the same floorplan in the other line. Some lines will have a west coast assembly plant and an east coast. But mostly they are built in the same plants, by the same people out of the same stuff.
I guess this gives you greater choice of colors and dealers, and you might get a better deal on one or the other.
And welcome to the forum.