im running a 600w hps sunsystem w/ a cooled hood at the moment. if you can keep your temp steady your good to go. your gonna want some kind of cooled hood on either light you decide to run in your space. im on the over kill side, my 600 is on 5 1/2 square feet, but i have very good ventilation. my exhaust is 265 cfm and surprisingly ive been running it now for a year with low complications. im doing a seed run right now with bcseedkings 6 kush and 2 blueberry clones. its going well, i only vegged them for a week and now they have been under the 600 for 1 week and 1 day. overall i personally prefer the 600. its easier on electric bills than the 1000, easier to cool than the 1000, and you can get the 600 closer to your plants than the 1000. IMO the 1000 really wouldnt give you a whole lot more when it comes to yeild than the 600 would in your space. if you want to expand your space the 1000 could be great.