Re the two organ sounds - it's not really surprising that they sound very similar, since they use the same basic sound sample
However, if you look at the composition of the two sounds, in the Sound Editor, you will see that besides the dominant sound (Slow Rotor 1), the Key Click Organ has 3 additional components (16', Organ Click and Fast Rotor 2) at lower volume settings. So there is a subtle difference in the two sounds.