Good sites can go bad, and those I don't recommend may improve.
They may be sold to a different owner who uses different standards or may engage in some of those shady practices to boost membership and use. You simply have to watch your back on any online dating site.
Always be wary of the signs of an internet dating scam.
We've all seen them - the ads show a bevy of beautiful women in your area, but when you sign up, you realize that the women were just ads that were geographically targeted to your search preferences.
Even sites that may once have been good can go bad.
It's pretty hard for any site these days (especially the big ones) to stop fake profiles and scammers from signing up, but I think I get what you're after.