I have stitched over 1,000 sphericals with Hugin despite also having a commercial package. Up to the 2012 version Hugin was just the easier and more user friendly version compared to other packages. Hugin is still my preferred package but I cannot recommend the 2013 version because the user interface is no longer as intuitive as it was and the introduction of pop-up windows or dialogue boxes to change parameters just adds so many more mouse clicks to the process.
Crashed constantly when going into quick preview mode. Online workaround to disable quick preview did not work. Uninstalled - not stable or reliable. I'll stick with manual stitching using GIMP ;-)
Hugin 2013.0.0 is dreadful! It won't load images until you specify stuff like lens type, focal length, focal length multiplier, etc. and it won't progress from there. With my crude cameras I have no idea what that information might be. My PC is Windows 7 64 bit and runs Hugin 2010 beautifully, it works like a dream and asks none of that technical information. Ask around for a copy of Hugin 2010 and you'll be in business, it's great!