Bests & Worsts Reviews from Amazon

After looking at the excellent ratings for this product, I purchased two units and installed them - one each in the bedroom and the utility room. One day, I was getting the toddler to sleep when I smelt smoke and something burning. Upon exiting the bedroom (which has one detector), I noticed that the house was full of thick black smoke from a "microwave cooking accident". There was no fire. The fact that the smoke detector did not go off bothered me and I did a bit of reading on the detection systems. Turns out that there are two detection mechanisms - ionization and photoelectric...and to cut a long story short, one needs to have both types of mechanisms in operation. The manual of this product pretty much says the same thing on page 6. However, it does not tell me which smoke detection technology the unit uses - information that I can use to purchase a different smoke detector with the other mechanism to compliment this one. I can only know how good this product is when it responds to something that triggers it. It did not pick up smoke that I picked up by smelling, and the documentation is inadequate. That is why I give it a one.