Hello. I'm from Holland (Vlissingen, Zeeland) and ordered the Paia Theremax-kit via www.theremin.nl. With no soldering expierience but with a little help from a friend i succeeded, and now own a custom-built Theremax! I built the case myself from aluminium and steel, and use two chrome tv antennas for volume and pitch. I use it in my band trough a series of effects to create some un-earthly noises, but i'm learning to play melodys on it as well. The Theremax is playable, but not a perfect theremin i guess. I find the volume antenna a bit slow responding, and the sound of the Tmax is a bit different then for example a Etherwave. I have no playing expierience with other theremins though...
The Theremax is a great project to build and a good introduction to the world of the theremin!