Yes, I did measure my late friends 800 D3 loudspeakers. This was the FR on and off axis.
The waterfall plot.
Impedance curve and phase angles.
The on axis response is quite good, and the off axis response mirrors the exis response to 60 degrees, but there are problems out at 90 degrees which is the black line.
This measuring technique is reliable above 200 Hz, less so below 200 Hz where there can be some room interaction.
As far as I can find I am the only one publishing this data. I can not find other measurements.
These speakers, replaced his 800 D2 speakers. The D3s sounded a lot better than the D2s. The 800 D3 speakers did sound as good as they measure and I would rate them a good speaker. He replaced his D2s after a prolonged listening session at our home while we lived on Benedict Lake. When he returned home his was out of love with his D2s. He was happy with D3s. Those speakers were the only B & W speakers I could have lived with. I have not heard their replacement, but published FRs are not encouraging.