Hi Elliot,
I have used all 3 induction devices (novaDreamer REM Dreamer & dreamMaker), I personally find my brain tunes them out quite quickly, but if I only use them occationally then I will get the odd LD from them.

I dont see any LD induction device on the page you link to, and I dont see how anyone could make one for 20 dollars. Can you describe what it is and what it does exactly?