I've been using the built in image tools for a while now. I've successfully backed up and restored with the Windows 7 tool many times (although there is a bug that requires switching to IDE in your BIOS before doing a restore unless you want it to take days).
I recently upgraded to Win 8. After I had my core programs installed, I did make an image (although it took me a few minutes to find the option since it's now buried in a weird place in the control panel). I didn't have any problems, although my OS drive (SSD) is much smaller than OP's.
2500k @4.2 (NH-D14), P8Z77-V Pro, MSI GTX 760 Gaming, 8GB G.Skill 2133, 512GB 840 Pro, Seasonic X-660, Define XL R2, Realforce 87u 55g, G400, X-star DP2710, Audioengine D1, Sennheiser HD598