I have worked with UShip three times. Twice I used people who had great feedback. Once, I took a chance. Big mistake. So I have learned: UShip is a wonderful service, but it is critical to read the feedback and go with your intuition. If it feels wrong, don't do it. There are lots of very nice people who work with UShip, which is why feedback is so important.
I highly recommend this website, but would never take even a lowball bid if the service provider did not have outstanding feedback.