Most people check our proxies for their Anonymity level on sites like whoer.net that uses certain checks to give you an Anonymity score. It's practically impossible to get a score of 100% (not even your home computer and IP will give you a score of 100%), but we are able to get a 90% score with our proxies. Here is proof:
To replicate this, you need to click the 'Your Anonymity" (in that green area) and follow the instructions provided by them to make you come across as more anonymous. Secondly, using an Incognito/Private Browser will fix any DNS anonmity concerns.