@rickoooooo well, to be honest, that's something I have a hard time measuring. I certainly don't notice that my emails go missing day-to-day.
But, there is one interesting anecdote. My wife was sending an email for my daughter's physical therapy, and the provider was using spamhaus. The email was rejected (but they sent us an auto response). I was able to look into it, and my IP had sent a packet to a honeypot. It turned out that my web analytics platform (self-hosted rybbit) had gotten hacked and was running malware. The best evidence I had was that it was an Iranian team.
I probably would not have noticed had it not been for self-hosting email and spamhaus 
. So, I'm greatful for spamhaus, and that I decided to self-host my email.