I imagine the lumenarc DE pendent is the best one available. Haven't seen any 400W DE bulbs, (I'm sure they're out there) and there is no true HQI 400W ballast to my knowledge. I believe that the people running DE 400W bulbs have found a ballast that will fire them, but it's not HQI.

If you go with 250, you can use a true HQI ballast (PFO makes one) and a 14K phoenix bulb. If you come over to see my set up that's whats on it.

Starfire glass is nice but still not as clear as high quality cast acrylic like Spartech polycast. Scratches are an issue, but even inside small scratches can be easily buffed out with micromesh while the tank is filled. My next tank will be an acrylic cube for sure. If they're built right they will last forever.