Hi, I already order 1 essay with Master pass guaranty but when I receive the work it seem to be very good and many words and sentences like a native writer did so I have to change something to fit with the my grade and the University will not think that I buy it. After I change it, i got a 72% means distinction. Its my experience with ukessays.com.
But when I search for their review it seem many different point of views so I think your work will depend much on who will write your work. If they pick a good writer, you will get high mark, otherwise it like a rubbish.
However, they are not scam.