I've been using uTorrent 2.2.1 Build 25302 [0] for a couple years now on Windows and it works great. The installer still has a few crapware offers that you have to click off, but if you turn off update checking the client will never bug you again. To install it on Windows 8, I had to disconnect from wifi and set Win7 compatibility mode on the installer.

[0] http://www.oldversion.com/windows/utorrent-2-2-1-build-25302

Tixati's the one I switched to once I got enough of utorrent becoming more and more crap-filled with each new release.

It's ugly as sin and the interface is a clusterfuck (even without the "haXXorz" green-on-black they use for their screenshots), but aside from that it's lightweight, does the job well and is very, very flexible.

Since uTorrent 3 has "ads" in it (uTorrent Plus offer in the app), I reverted to 2.2.1 and never upgraded anymore.