sure its good, work out what umol/m2/s would be for a 600 HPS.
I pilfered this from some www.internetty.site
Roughly these are a few examples of recommendations for a high light recipe of around 700 µmol m-2 s-1. Calculations made with 10% reflector / wall losses:
400W a) – 1 x 1 m – 1 m2 at a ppfd of ~ 650 µmol m-2 s-1
600W b) – 1,2 x 1,2 m – 1,44 m2 at a ppfd of ~ 690 µmol m-2 s-1
1000W c) – 1,5 x 1,5 m – 2,25 m2 at a ppfd of ~800 µmol m-2 s-1
In practice levels can be lower with different reflectors (open reflectors will have more stray light), older reflectors and a lot of wall influences. Other lamps may result in different densities.
a) – Philips GreenPower 400W 230V – ppf 725 µmol
b) – Philips GreenPower 600W 230V – ppf 1100 µmol
c) – Philips GreenPower 1000W 400V Electronic – ppf 2000 µmol