Shereaza suffers from the same problems as eMule (Gnutella P2P), but it does have an excellent record of non-bogus apps.
The trick to getting Shareaza right is to ONLY connect to Gnunella2. Gnunella1 is so old they only have CP/M apps on it , and connecting to eDK2 will only cause your uploads to inclease by 1 zillion percent while only increasing your D/L speed by .000000000002.
No matter what your speed it set to in the connections options, make sure you limit the U/L bandwidth to about half of your advertised speed (i.e., for an ISP advertised up speed of 256 K/bs, set it for 128 K/bs or 12 K/Bs), as too high an U/L speed will choke your D/L speed.
Also, make sure your hardware firewall and router (if you have one) is set to allow Shareaza to use the default port of 6346 (TCP and UDP).
The speed issue is what keeps the really good seeders from putting warz and movies on Gnunella. Right now the hottest thing going is the private FTP sites, that work much the way the old Jolly Rodger warz boards did in the early '90'z. You have to upload in order to download (most have a very generous ratio of 10:1), and the speed is great (about 80% of what your connection is capable of), and the D/L's are all verified ones.