Did you see any real differences between using COBS and HIDS? I've checked on Alibaba you can get those chinese cob lighting units pretty cheap. But I've already bought both MH and HPS 600w grow lights ready for my raptor hood when it arrives.
Ordered this bad boy too
"The awesome Dominator XXXL grow light reflector from Sunlight Supply is the largest air-cooled reflector in the world, and is ideal for those needing a large spread of light even when suspended at a low height.
This is THE ultimate air-cooled reflector for 600watt and 1000watt lighting systems.
Constructed to the highest quality using photometric data, it has 95% reflective textured German aluminum interior, which offers excellent reflectivity and diffusion. Completely sealed - features double gasketed glass and hinged frame to hold glass tightly in place."