For the most part I have been pleased with the effectiveness of the Feline Alarm Clock. There are, however, significant improvements needed to make this product user friendly. For instance, there are several alarm options: "horking up a hairball", "tummy trampoline", "weight on a full bladder", "purring in your ear", "licking your face", "chewing on your fingers", etc. If you have two of these alarms, you can also get "cat fight on your chest". However, there is no option to choose which one you'll be awakened by - it's entirely random. The alarm cannot keep accurate time. Sometimes it goes off too late, but more often it goes off too early and thereby cutting in to a REM cycle. There is a tendency for the alarm to sometimes fail entirely even though there has been no interruption in the power supply. Many a morning I have awoken to find that the alarm has actually left the room entirely - what's that about?
I have to admit that despite its serious shortcomings, I am loathe to return my two versions of this product. Despite the lack of reliability, I find its other features (lap warmer, cuddler, familiar, etc) to be well worth the investment.
In summation, I would love this alarm clock if I could set it to a consistent time and option. Until then, you will definitely need at least one back up.