Increasingly, designers seek feedback on their designs from crowd platforms such as social networks, Web forums, and paid task markets which demand different amounts of social capital, financial resources, and time. Yet it is unknown how the choice of crowd platform affects feedback generation. We conducted an online study where designers created initial designs and revised the designs based on crowd feedback. We measured the quantity, quality, and content of the feedback received at two iterations and from crowds driven by social status, enjoyment, and financial gain. Our results show, for example, that task markets yield more suggestions, online forums provide more process feedback, and social networks give the most suggestions without payment. We contribute an emergent framework for crowd feedback selection, opportunities for enhancing feedback services, and an experimental platform that researchers can adapt to reduce the burden of conducting online studies of design feedback.