... and I still have my HF100. Actually I have two because I bought a second one shortly before they disappeared from the market.
I don't have the impression that the new models offer any significant improvements in image quality. The only thing I miss is full manual control but if I have the urge to upgrade one day I will rather buy a real pro camera with built in ND filter, professional audio, waveform monitor and dedicated controls. And should this camera shoot great stills and video and have a larger sensor I'd be more than glad.
But until then I enjoy the compactness and ease of use of the HF100. Forgive it it's quirks and try to make the best of it.
I learned a lot about video in this three years and I'm glad some posts where also useful for you.
I close this blog now and move on. Be well.