I would not trust a service that has a “Backlink Maker” such as this:-
Backlink Maker
Generate Quality Backlinks With the Click of a Button
Put your best SEO foot forward and generate a large number of high value backlinks ina matter of seconds. Simply enter your website below and click “Make” to watch the free backlink maker tool do its job!
As if it were so easy 
It also has a Plagiarism Checker and an “Article Rewriter” AKA Spinner! 
To all contributors: please read post #26 before posting.
(I don’t want to post again what I’ve said already… )
I suggest Duplichecker.com and Small SEO Tool’s Plagiarism checker. For cross checking plagiarism, I use both tools.
As for me, Small SEO Tools doesn’t seem reliable. It has a lot ads on its main page aka “Boost your ranking on Google for 15$” , “get 100 free backlinks to your site” 
Besides, its checker requires CAPTHA, has limit in 2000 words/1 search, and just parsing your text into parts and search for plagiarism using Google.
I use this plagiarism checker: https://unplag.com/ And I want to admit, that it’s worthy to use!