I've used it twice in the past for logo work, with good results both times. Comparable to using a professional design shop, which I've also done multiple times.

I've used it twice in the past for logo work, with good results both times. Comparable to using a professional design shop, which I've also done multiple times. However, some notes: - You'll want to pay more than the average to attract a wide range of designers. It's still cheaper than a professional designer, but don't think you can lowball the 99designs market and still get good results. - 95% of what you get back will be utter crap, and responding to this can will up a lot of time, much more than working with a professional design shop. - Both times my winning designer was someone from southeast Asia with a shaky grasp of English. Perhaps my experience was atypical, but I suspect you'll have to deal with this as well. - Some of the nicer-looking stuff was ripped off from elsewhere with the colors re-changed, which I only caught through some image searches. You may pick a winner you don't actually own, and I don't know how to guarantee against this. - In both cases I had a good sense of what I wanted in advance and provided very specific instructions to the designers. If you're looking for someone to brainstorm ideas your results might vary. - Yes, it's spec work and since I wouldn't work for spec, asking someone else to do it is sort of problematic. But no one's forcing the designers at gunpoint to use 99designs, and there's no denying the cost difference (although it does come with significantly more hassle.)