Hey Bruno!
Also make sure in the "Setup" tab to mark "Anonymous visitors from ISPs" as hidden, which should help a bit although still lots of ISPs slip through.
My experience with this report is similar -- it is interesting but has limited use unless all your prospects are from big companies that have IPs registered to the company name.
Although apparently we have over 2,200 anonymous leads from Fibernetics Corporation!
😉If you discover another tool that does this much better let me know, I'd be interested.