The plagiarism check, which is the only reason I used this site, does not pick up a good number of word-for-word quotes, from highly cited articles, which are picked up by the turnitin checkers used by universities. I work at a London university and checked this. If you are looking for a site to allay fears of inadvertant plagiarism, writecheck.com is useless. I have emailed them a number of times asking them about this and have recieved no response. Waste of my money.