I didn't think you'd have any trouble selling that speciosa, it was gorgeous.
My experience with red dragon is the following:
It is quite adaptable to lighting (within reason) and flow but will grow very differently depending on the amount of light and flow.
I think under t5, it will handle everything from low to high light, under mh, it may not handle intense light quite as much.
It will be more red with higher light (when not over exposed) and it will be more pastel under lower light.
In terms of flow, it is like most corals; it'll grow more open, delicate and irregular under light flow and more clustered and dense under high flow.
Where I have found it to be less adaptable is when dealing with system instability. Like nutrient or main parameter swings.
I have a couple pieces doing very well at the moment but in the past, I have had pieces that grew well and then rtned over night for no apparent reason. Like all dragons, it can start rtning and then just stop, again for no apparent reason.
They will eventually encrust but they take their time, so glue it well.
I have always thought of them as exactly like ice/fire echinatas for lighting and system requirements-delicate and finicky when they don't want to cooperate but tough as nails when happy.
So, if it were me, I'd be more concerned with flow than light. It is pretty whether it is pink or red but it is way more attractive when it can grow out in an irregular and open form..