[Elecraft] KX-1 80M Question

[J]

I'm considering replacing the 30M module in my KX-1 with a 30/80M module,
and had a few questions first:

 

What chances of contacts with 4 watts on 80M. using a typical end-fed
antenna suspended from a tree or hotel balcony?  (Seems like higher bands
are easier at QRP)

 

My KX-1 has the KXAT-1 ATU.  Will the KXAT-1 also attempt a match on 80M?

 

Has anyone had success with ONE antenna and counterpoise length that will
load properly on 80/40/30/20 using the KX-1/KXAT-1?  (I'm thinking a length
which avoids High-Z on these bands)

 

73, Jay

W6CJ