Ask YC: Should you take 'dumb' seed money?

When looking for seed funding, what would you do if the only available option were a family or friend (not a 'real' angel investor)?

I ask this question because it might seem tempting to simply take the money and get cracking. But, would it be better practice to force yourself to raise a real angel round? The idea being that, if you can't get an investor to commit, either your idea is bad or you won't cut it as a founder.