Eddie,
I said the Nv4k & mk1 Vortex are so close in cone & monopole length that the only things making them different are the tube taper schedule & diameters,
if you don't include what makes them different they are the same antenna in nec.
you will never see the claimed 2 s-units increase over the Nv4k in any same pole same timeframe test,
its nonesense & anybody that ever tested different 27mhz antennas on the same mast knows it,
something other than the antennas themself screwed the test up,
looking at oggy's video you can see the gamma is closer to the monopole than the 1/4wave cone versions,
You said you had to use a longer dogbone & the models look to have the gamma spaced further from the monopole,
one model has a long gamma strap putting the gamma out near or past the radials,
relative tube diameters & spacing determine the characteristic impedance of the gamma section,
My antennas are using about the same angle as the 27mhz version & that's no problem with the 1/4wave cone,
it tunes ok with more than one combination of gamma tube/rod
The Q82mk2 gamma is not wide spaced like your models
it looks to start about the same as the radials at the bottom & sits parallel to the monopole,
I have turned gamma rod clamp over so the gamma sits more parallel to the monopole but i have not tried tuning it yet.
