I planted a few seed last week and put them under 2x3 modules. I also put a batch that I planted a month ago under the lights as well. The results are tremendous. The month old seedlings were pretty slow growers and rather weak, one seedling came fresh out of the earth shortly before I put it under the light modules and it outgrew its brother that came out 2 weeks earlier in a matter of 5 days.
Here some pictures. The first 2 are made after 6 days of planting the seeds (or 4 days after they actually started germinating). The last two are made 2 days after the first 2 images.
After 6 days
After 8 days:
Update after 11 days: