I saw The Hobbit, in HFR 3D and I liked it.
I did a lot of 24 vs 30FPS research as I went through the effort of making my first and second home theaters (Projector, HTPC, 7.1 sound system) 24 and 30FPS friendly. In my reseach, I came across a lot of discussions regarding 24 vs 30 FPS content. The only impression I had was that 30FPS content was nearly always made for TV and, that sci-fi content often looked cheaper but, I always attributed that to the quality of the sets, costuming, lighting, etc, given that they often have lower budgets. This may be why a lot of folks associate high frame rates with 'cheap'.
After a recent discussion with a coworker, I started to think about the 24FPS vs HFR 3D choice this way:
When you see a movie, do you feel it should be presented as a story or, do you wish to feel you are in it?
The way I see it, HFR 3D is simply too realistic to give one the feeling of a presentation. There were only two occasions where I saw something I probably would not have seen in a 24FPS format:
During the trek through the mountain pass (before, and during the stone giant fight), I could clearly see the rain drops hitting the rock wall, and in the foreground but, I never saw a raindrop hit a face.
During some of the outdoor, full daylight scenes, the texture of the screen could be seen in the sky (might've just been this theater but, I suspect that it's the result of our eyes receive more light at 48FPS than 24).
I've always been one for feeling immersed in the film. I hate noisy crowds (which is why I DIY'd my own theater), and other distractions. The 3D use in this film added to the immersion- there were no over the top tricks with it. so, in the end, this format did it for me.