600 vs.1000 watt setup?

Currently have two 400 sodiums and want to add either a 600 or 1000 in between (switchable HPS an MH). I realize heat is one factor in determining which route to take. Any suggestions on which way to go both positive and negative?

I would go with 600W. happy grow

Unless you are growing commercially a 600 should be more than enough for you.

Trying to decide between ipower 600 ,dimmable (3 adjustment settings) 600 and vanilla 600 (one year warranty included) for basically the same price ($179). Includes reflector, electronic ballast, two bulbs (MH and HPS), two pullies, timer. Any suggestions