1-carboxy was the active in USP's old REM product, and I bought some in bulk from a board sponsor a while ago. It works pretty good as a sleep aid, it knocks me out within about 30 minutes of taking it. I seem to get a good, deep sleep with it and wake up feeling refreshed, especially if I only get around 5-6 hours.
Definately recommend it for nights you know that you won't be getting a full 8 hours in.
I also remember that USP stated there was a moderate HGH release, especially in conjunction a full nights rest; but I could be mistaken.