The problem I've faced: UI becomes seriously slow and unresponsive when I have more then like 3-4 active seeding tasks for a long time. Same for leeching. Also, if I stop downloading task of some big file - UI freezes (probably until data fully flushes onto disc). And for me it's a problem which I did not face with other clients.
Windows 7 SP1 x64, latest updates
Intel i7 4770k @ 4.4Ghz
16 GB DDR3
100MBit Full Duplex connection (Up to 1Gbit to peers from my country)
I use 1GB of disc cache + enabled disc writes caching in windows.
To me it looks like if the app's UI thread is used for disc operations so that they block it which results in awful experience with UI.
Any help or thoughts are appreciated.
For now I'm gonna test it with disc boost service disabled.
P.S. For some reason uploading small sized jpg attachments fails each time. Here are screenshots with settings and log: