I actually agree with David. I have two designers I always pay as low as I possibly can, I always ask for them to do as much as I can get out of them without quitting on me mid-project, but I ALWAYS pay for work... On-time with either certified check or direct deposit.
And no Equity sharing for non-programming work. ESPECIALLY with my own projects.
I'm launching a site with about 120K in marketing capital this week on several aff networks and I would NEVER squander away equity for graphic design.