600 is more than enough, my only concern was that she's got "trees" around her. So, between the light being so far away and ther ladies looming over her, I was worried there wasn't enough light penetration. But, like you said, the bulk looks good and I've had plants look way worse early on and still pull 2+ zips. Just being a bit antsy considering it's my first DWC grow. But I have high hopes for her.