It is also interesting seeing how much difference headlight aiming makes. Critical to match with your driving needs.
The comparison is good in one way and not in another. The D2's in this case seem to be set up as flood/fog. Yes, they are lower brightness, but, the goal is different.
Most of my need is for visibility with a little extra side light. So, I got my flashlights and put them on. Not quite as bright as the Denali's but looking at the bike they are the same. The triangle is very important IMHO. The best part is the flashlights cost $20 with $10 worth of voltage regulation (they are 700 lumens each).
If I were riding off road or I needed absolute reliability I would definitely get Denali's just for the construction of the lights.
But, I can live with a light going out every now and then or needing to rewire them at some point. At the same time mine have almost 15k trouble free miles on them at this point.
My brother, OTOH, will get a set of Denali's for his 2014 GS. Just like he has a set of Tourtech luggage on order where my Guzzi wears $40 ammo cans