Other than my own experience, I can offer no physical proof that any type of grow lighting is any better than another. I believe much of it comes down to needs and preferences.
One theory that I do attest to strongly though, is plants that are bloomed under LED grow lights, produce more trichomes and often times produce them a week or two earlier than HPS or CFL. To be fair, I can tell you that it seems sometimes, LEDs can take a week or two longer to reach peak bloom than when under HPS.

Here’s a peek at 4 of the 6 girls in the Bloom-Room, under the Pro-Grow 400:

Nirvana Auto Flowering Marijuana Seeds

Day 24 bloom - Aurora Indica #1

Aurora Indica #1 - Trichomes and dank aromas develop on a "hammerhead" top.

Aurora Indica #2, Day 17 bloom

Aurora Indica #2, day 17 of bloom. She pulls a strong Afghan phenotype from her heritage.

Mystery Sativa "Bebe", Week 7 of blooming

"Bebe" our mystery Sativa, week 7 of budding, continues to pack on weight, red hairs & trichomes

Nirvana Auto Flowering Marijuana Seeds

Day 17 of budding for this Blue Mystic

Blue Mystic "G" at day 17 of bloom.

Any open space we had last week in the Bloom-Room, is quickly being filed in by all 6 plants.

  • Aurora Indica #2 is very short & compact, as I could not get her to stretch at all, but her tightly node branches are filling in with fat white hair clusters.
  • Aurora Indica #1 is creeping along & filling in nicely, already very sticky, her sweet aroma only adds to her appeal.
  • Bebe, the mystery Sativa is filling in as her white hairs gradually redden and her branches swell.
  • White Widow #3 is stretching & growing & blooming, A very aggressive grower since beginning to flower, she may be a big producer.
  • Blue Mystic “D” is another big grower, a little slower to bloom than “G”, but a very big finisher.
  • Blue Mystic “G” will probably not produce half of what “D” will, but her appeal isn’t in her quantity, but her unique qualities.