I am seeking opinions as to the performance of such an antenna

The opinion is it will be a great antenna.

The modeling facts a
It will give you approx. 11 dbi gain, and 13 db f/b. It will have a feedpoint
Z at resonance (7.025 MHz) of 33.3+j0.

The gain will vary from 11.24 dbi at 7 MHz to10.2 at 7.2
The f/b will vary from 12 db at 7 MHz to 9 at 7.2 (peaking at 13.6 db at 7.05
MHz)
The feedpoint Z will vary from 30-j6 at 7 MHz to 50+j33 at 7.2

The parameters of this particular antenna a
ht above ground 23 meters
Length of one side of driven ele = 10.3 meters
Length of reflector = 10.66 m
spacing = 6.7 m
angle between legs=120 degrees

There are of course hundreds (no, thousands) of different combinations of
these parameters that will give different performance characteristics. This
one is not necessarily optimized for any particular objective.but it is close
to what you said you want to build. Naturally I highly recommend that you
model your own antenna and see what changes affect what !! I'd be happy to
give you my 4NEC2 file that I used to determine the above. It and the program
are free. It would be a great starting point for you.

Interesting observation - I have made similar trial runs for others who have
inquired on this newsgrouop, and the tower reflector, and always offer to send
my file and offer to help get them started in modeling (10-20 minutes on the
phone with both of us looking at the same data in the program). To date no
one has either acknowledged my postings or accepted my offer!! Is modeling
that intimidating? I learned what little I know by hacking around for hours.
I could teach someone what I know in 10 minues if they were interested and
computer literate, short circuiting many hours off the learning curve.
Modeling is fascinating. All the tradeoffs that Roy just aluded to can be
studied easily on your own PC without taking the word of others. You can
change the angle, the height, the ground under, the dimensions,the size of
wire, the spacing. You can examine the gain, f/b, pattern, imedances, takeoff
angle, bandwidth.
And I will GIVE you the simple little file that you load into your own free
copy of the modeling program that allows you to do all of this.

Rick K2XT