yes, the Spectrolux and the Holmes-Wright Test are quite similar, however there are some differences:
1. the HW-Test uses 5 different lights (white, yellowish green, green, two shades of red), the Spectrolux Test uses 6 different lights (two shades of white, green, pale green, two shades of red)
2. Viewing distance to the lantern is approx. 5m at the HW Test, but only 3m at Spectrolux Test.
Oligoe, whishing you the best, but in case you fail, i would encourage you to try the Holmes-Wright Test. I failed bot the Beyne's Lantern AND the Spectrolux Lantern, but finally passed the Holmes-Wright Test in Gatwick. So it is possible, even if doesn't look like it!
Viel Glück!