Sal M. Onella wrote:
"How are they at VHF/UHF?"

Arnold B. Bailey in "TV and Other Receiving Antennas" wrote on page 528
specifications for a 200 MHz rhombic antenna. It may be scaled for
another frequency. For 20 MHz, multiply dimensions by 10. It is four
straight horizontal wires (no. 10 AWG) each 36 ft. long, separated 18
ft. at mid point, overall length 31 feet. Transmission line is 300-ohm
balanced twinlead. Reaistance at center frequency is 600 ohms as is the
termination resistance. Gain at centerfrequency is 14.5 dBd (or less).
Frequency bandwidth for 1 dB down is 30%. For 3 dB down, it is 100%.
Polar pattern shows lots of side lobes.

Best regards, Richard Harrison, KB5WZI