azureus is resource hog but generally its distributed database can bypass some sites security like loggin in to peers when you dont have access, and it has more sources to get seeds/peers ie db,dht,tracker,onion, etc. but i will say azureus is a resource hog, utorrent on the other hand runs with virtually no resources but its simple, however since it is now owned by anti-p2p i wouldnt use any version 1.8.1 and above, generally i max out my top speeds at crikeym8.com no matter what client i use, but i say azureus if youre having trouble connecting to peers but thats all it basically does, it will get you more people to dl from, mostly speed comes from great seeders with 100mb/10mb speeds i don't think i can post sites for you but generally public trackers like isohunt, and now demonoid have suck *** speeds and dupe torrents everywhere, also beware of btmon since most of the torrents there are fake. Try getting into a private tracker