The OP uses the Scorpion Diablo's as stated in his first post which is what I was giving my opinion on and passing yours along to. My personal setup is ran according to my growing style, setup, goals and also what I've found works best for me over the years of experimenting so I'm good there. I'm not the one looking for suggestions. I don't use the Scorpions personally, I've built my own lights using 2 of their older 320w XL qb's kits which basically gives me 640w and 6 qb's covering a 4x4 area which obviously isn't the same as the Scorpion Diablo's, but in a way similar. As far as your opinion on the bar style lights being 18-24" above the canopy for flower I gotta disagree with you there. Both from working in a commercial facility to how most use the bar style lights and how we plan to after this years last run of the qb's is to be able to run the lights CLOSER to the canopy for many different reasons, but still getting that even light spread and the numbers we want the plants to see. For us it's more like 6 -12" or sometimes even 6 - 8" depending on the light fixture, quality and performance itself. But anyways, not trying to take over the OP's thread on all this lol. But everyone has their opinion and like you said to each their own... OP honestly I wouldn't over think it man and just start at what HLG recommends and use the onboard dimming. They recommend it for a reason you know and is there really any reason not to start there? Like what was the reasoning to even asking if you should raise it? Are you seeing light burn or something? If there's no reason why you would want to or need raise or lower the light in the first place I guess I'm asking? But for whatever reason if you do then just pay attention to how the plant responds and make your own decisions based on your setup bro. There's 100 different ways to approach it and I'm sure you'll get 100 different answers too lol. If you do wanna get it more dialed in though I would recommend looking into a decent PAR meter like I was saying before, then you can see exactly what your plants are getting at any point of the canopy which would actually tell you if you do or don't need to adjust the light at all. Worth the $150 in my opinion, but that's all it is. Either way keep us updated on how them Scorpions are doing and what your producing over there!