(09/07/2009) - The 250 watt Radium is tough to beat on the HQI ballast. Color is whitish-blue and will work fine as a stand alone bulb, but looks even better with a few actinic VHO's. I find these are as bright to the eye as the 400 watt Radium and they last close to a year on the HQI ballast.

(10/20/2008) - These bulbs have a nice white/blue color when run on an HQI ballast. I was shocked however with the poor craftsmanship being a German made bulb! If you lightly shake the bulb, the contents clang against the outer glass envelope. The internals were crooked in both bulbs, one of the arc tubes is at an angle! The glass envelopes on both bulbs are misshapen as well. Hopefully they'll last, being so poorly made. Out of 5 brands of metal halide bulbs I've used/seen, these are BY FAR the worst made. I'm giving this bulb a 1 because of quality, and a 5 for color.

(03/09/2007) - If you like a blue tint, but just the right amount, these bulbs are for you.