We ran our own engine at 73 directories in a single session and published what happened. Twenty came back as confirmed submissions with a success signal we could actually verify. The other 53 landed in review queues, wanted payment, rejected us, or failed silently in ways that were invisible until we went looking.
That ratio is the honest shape of this work, and it does not improve because you do it by hand. Every site wants different fields, a good number hide a captcha, and plenty accept a form and never publish anything. Doing 50 by hand is a working week, and at the end most founders still cannot say which ones went through.
Read the full write-up, failures included