Yes I do, before listing a site I use a search engine to see what is said. But it's up to the person to make the due diligence too. I'm not a baby sitter and I can't test each mixer every week to check if it's still working
I posted a list, not reviews/suggestions, otherwise the list would be empty with only 2-3 services perhaps. I wanted to stay neutral.
Also scammers usually mix bitcoins correctly at the begining, to attract people, but once more people come (more bitcoins) they decide to scam and leave.

As a community, everyone can contribute in this topic to help others, and that's what you did when you posted.