We had this conversation the other night under a 9 foot Diamond light.
The diffusers are pointed straight down so the light doesn't come down on the table the same way it does on a regular light that shines moreso from the middle of the table. On the Diamond light, the edges of the table, especially the end rails, are hard to see for cuts. I've witnessed so many good players who, at first,miss cuts along the end rails, usually cutting too thin, in my observations. After a while you get used to it and the negative effect is reduced but is still there if the player hasn't figured out that he has to take an extra second of aiming those shots.
My opinion from limited observation.
Those lights sure look nice, though.
Jeff Livingston