my friend he4re is the botom of line of all of this :

1. gnutella has less users than edonkey so gnutella is faster
2. edonkey has much more users than ne network so it has almost everything but... its slower
3. lime wire , bear share , cabos..... etc use just gnutella network so u can download very fast from them (notice that lime wire use bittorrent protocol also and this 1 is the fastest child of all).
4. sheraza use both gnutella and edonkey so if u have user in queue belongs to gnutella u will notice that u download faster from him and the opposite for edonkey .
5. the last thing try to rise your upload ratio a little bit it will help believe me

thank u my friend hope u will find your answer .