[Question] I still have yet to buy the Chameleon EMCOMM II V2 antenna that I had set my sights on. May have to wait until sometime next year for the funds.

Regardless, I am still looking at how folks have deployed this EFHW antenna. Some have replaced the 60ft wire with something longer to make it a random wire end-fed that works better at 40 and 80m. Some have used 75ft of wire, some have used 80ft and longer. What are things to consider when choosing a length of wire? Can I grab any length of stranded wire from Home Depot and attach it? How would counterpoise wire length be affected (user manual recommends 40-50ft, depending on configuration, with the 60ft main wire)?

[Answer] For the best performance on 80m, your EFHW really needs to be 130′ long.  And, it’s not going to be able to tune well for both 80m (data end of the band down by 3.5mhz) and 75m (phone part of the band up by 3.9mhz).  This is just physics.  If you have a good tuner, you can likely tune an EFHW that resonates down near 3.5mhz up on the phone band at 3.9mhz.  Palomar Engineers has got some information on the various wire lengths of their “bullet” end fed antenna designs… Learn more   Learn more >

That supplier also has an EFHW with a 95 ft wire that they claim tunes on 80m (Bullet 8006). It has a 4:1 balun (or unun or transformer, not sure what the difference is). Is that wishful thinking without a 130ft wire?

95 feet of wire could be used to put out a signal on 80 meters.  95 feet is not a half wavelength on 80 meters, it is longer than a 1/4 wavelength.  I would call it a random wire antenna.  Manual tuners can tune random wire lengths.