[Elecraft] K3 sub receiver

[ke4d at att.net]

My K3/100 kit arrives tomorrow.  I did not order the sub receiver. I have only a vertical here and have some antenna restrictions (height) I use a SteppIR BigIR and it works great for me with my height restriction.  So, unless one of you can explain to me why I should have the sub receiver with only one antenna, I'm leaving it the with one!  I'm sure I don't understand receiver diversity since I never heard of it until recently.  Guide me!

John KE4D
K3 SN ????