Hi TimF
They are indeed spindly and not solid. The foot, stem and top plate all bolt together nicely and the speaker bolts onto the top plate with felt discs coupling the interface. The foot is such that it wont allow the speaker to topple and has adjustable felt tipped footers for levelling. So, sturdy enough!
The speaker will sway if nudged, but this compliance is designed in to facilitate the effect that the floor standers get with the swing bases. It's totally counter intuitive at first, especially after investing in Gaia's for my previous speakers, but the system works and the result is quite remarkable.