I've seen it in action - it works but you have to be quite careful when building it. There's a bunch of gotchas and it changes over time so you have to be very

I've seen it in action - it works but you have to be quite careful when building it. There's a bunch of gotchas and it changes over time so you have to be very very sure you're looking at the instructions for your actual kit. Also it isn't self-contained - you need a computer attached to it the entire time you run it. Still, the price point is amazing and it does what it says on the tin. (I don't own one but I've seen it in use).