Wow. This looks like just what I have been looking for. Something to give me an idea what my CO2 levels are in my tents. I have been trying different ways to introduce CO2 to my tents however it is hard to tell which ways are working better as I do not have any kind of environmental monitoring as of yet. These both look great. If you are still looking for a guinea pig please sign me up. I would have no problem providing feedback, reviews, pics etc. I think they both look great. I could even test them against each other as I have 3 tents right now I am currently running. I hope I get picked.