At the risk of stating the obvious, radius is half the diameter - so the radii of these 3 sizes are, respectively, 2'6" (about 760mm), 3'3" (about 990mm) and 4'6" (about 1370mm). Now, LGB R1 is 600mm, R2 is 765mm, R3 is 1175mm - so your smallest Aristo curves are pretty close to LGB R2, and the other two are respectively slightly smaller and larger than R3.
Don't know if that helps at all?
Jon.