They are all good.
The great thing about the internet is the ability to share info.
The bad thing about the internet is the abiltiy to distort shared info.
Yes - we've seen some failed filters. But our ability to share across the oceans (literally) the kind of info that used to only be seen in a garage discussion with your buddy makes for a tainted view.
There are only a couple of folks here that actually work in the filter business that I'm aware of; Motorking and Pete C. And I'm not really sure the exact capacity they function in to be honest.
What we know is that we don't know the statistics of failures. We don't know the total volume produced, nor the overall failure claim rate, etc. For all we know, the failure rate may actually be in decline, but our intense curiostiy and ability to dig into everyone else's business makes for salacious info.
If you watch the news every night, you'd swear that violent crime is on the rise. But the reality is that statistic has been in decline (Per DOJ/FBI records) for a couple decades, actually. It is the intense ability to broadcase problems nationwide and in your face with immediacy that takes your attention away from a calm, rational approach.
Same applies to filters; this site helps share info that you'd never otherwise see, and the repeated exposure makes for ultra-sensitive discussion.
But don't let this get overblown here. You're welcome to jump to a conclusion; I can't stop you. But I'm not following you off the cliff until I see unbiased, well founded, hard data.