The general consensus of all that I have heard and experienced over the
years is that if you can get the beam up at least 1/2wl, what you lose in
lower take-off angles than the higher dipoles will be more than made up
for with a. the beam gain, and b. the steerable directivity (including
front-to-back). However, you may have a good opportunity to make A-B
comparisons by installing both. The dipoles can be your back-up antennas
if Murphy hits your beam assembly and also allow you to see what really
happens at your site. When I first moved to this QTH, I threw together a
hand-rotatable dipole for 10-meters, and just the ability to move the
nulls and the broadside were very welcome indeed until something better
could go up.
Hope this is useful.
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