Flush shouldn't hurt, and the sooner you pull it the more immature seeds you will have. If this is your first time, you will probably be surprised at how many seeds you get even on a tiny plant! You will have mature seeds at 4 weeks post pollination but will have more if you wait a little...
MtRainDog,
Do you use that soil mix? I have read that thread many times, seems to easy. But if you look at water only soil mixes from StankBros or BlazeOneUp those guys seem to do great in simple soil mixes that are water only as well.