I was an avid Firefox user until I upgraded to Win 8. I heard IE had improved a lot and was on par in many ways with other browsers, so I thought I will give it an honest chance and I havn't installed any other browser since.
So IE11 for me, syncs nicely with my Surface RT that doesn't really have much options. If only it synced with my phone too, but oh well.
Chrome is a resource hog.. I use IE11 on Windows 8.1. That browser is lightning fast and has bookmarks sync and tab sync (finally). Plus I like the integration into the OS, being a Microsoft product of coarse.