I'm 4/5, meaning that of the five projects I've backed, four delivered what they promised and one turned out to be, if not a total scam, at least a project where the creators lied about how far along they were in prototyping and currently haven't posted a project update in almost three months -- I'll give them the benefit of the doubt that their intentions were good, but they quickly got over their heads so they took the money and ran. (Here's that project:
https://www.kickstarter.com/projects/wicoz/milk-nanny-the-wo... )
I was very frustrated by the degree to which Kickstarter would take any responsibility after the project clearly started going south. Even though this project was a "Staff Pick!!", implying, to me at least, a higher quality project than normal, they didn't seem to have any interest in holding the creators to account. After they wouldn't refund my money, I did a chargeback through my bank. I then got a message from "Kickstarter Integrity" scolding me and telling me they were blocking my account from pledging for 30 days and telling me to tell my bank to cancel the chargeback! These guys take the money and run, and my integrity is challenged! It was pretty friggin' insulting.
The experience might not have turned me off of Kickstarter forever, but I will definitely be more cautious before throwing my money at any other project on the site. It would be great to see a KS alternative which is willing to hold vendors more responsible.