We use CO2 in our lab and a number of years ago we thought it would be great to buy a dry ice maker (basically, the same unit shown in the link), since we only had sporadic need for dry ice. While the unit does produce small quantities of dry ice, it is very inefficient and not worth the bother for the small amount of dry ice produced. We got rid of the unit and pirate some dry ice from another building if we need any. Save your money.

Pete