Thanks for all the info.

I have not bought anything yet. I have found a few ballasts that are switchable. That is actually not an issue.:thumbsup:

However I read somewhere that the best lighting was both MH and HPS simultainiously for all stages. Under that was MH for growth and HPS for flowering. However both for all is said to produce the best and healthiest plants. This lead me to finding these bulbs. I really like the idea of both, so I guess the question would be,..

With only a 6 foot by 10 foot room running 2- 1000w, (consisting of two duel arc bulbs). Would that NOT be enough regardless of the loss caused mostly by the bulb being 1/2 the size of a normal bulb on each half?

OR, Would this just be way overdoing it?

Seams most things I've read, agree with slightly less then what I'm suggesting for a room this size. To me it seams a little overkill to compensate for the bulbs should fix that issue.

OR, is the spectrum on this type of bulb just not right?

Again thanks for the replies