so its not the most accurate since i couldn't be fucked moving my plants and making a grid, but i did it as accuratley as i could with some string across so i was measuring at 12" across the board.
i also turned off my other panel so this is accurate for 1 of my panels, which is 6 of the 1m strips, for 300w. panel is 20" wide and strips are 2" apart.
i took 4 measurements each "line" so first measurement under the furthermost strip, then middle, middle, edge again. did the same along the panel (strips are 1m long)
bit lower then i expected the results to be, but this is again just 1 panel, no reflective surfaces. when i turn the other panel on its a fair bit better, and i will have 4 panels in here soon so i'll do measurements across the board on all of them.
also just for comparison, this is LUX on my phone app reading between 30-35k LUX across the same area.