Although these campaigns are good as the participants get rewarded in btc and eth that are widely accepted and are almost as liquid as cash but at the same time i have seen that usually such campaigns pay very less as compared to open campaigns as we can get much bigger reward but yes we will have to wait for long time to achieve our target price if the project is good.
exactly what i wanted to say about this. I also want to add some more information about this is that there more possibly of project to be scam or fishy because of increased number of the project in recent months being disappeared after collecting money.