I bought this product from Amazon last year and can say that it works perfectly and as advertised. I have a set of Corsair Dominator GT CMT16GX3M4X2133C9 12GB 2133Mhz DDR3 and did not have any problems.
Here is a quick list of Pros and Cons for this product:
Pros:
1) Works exactly as advertised - shows temperature and memory load activity for each memory module
2) Detailed instructions are included for installing the CMXAFPRO onto a Corsair Airflow 2 fan (not included)
3) Adds nice 'bling' to your computer setup
Cons:
1) A bit pricey considering no Corsair Airflow 2 fan (CMXAF2) is included
2) Only works with Corsair CMT and CMX memory products
3) Limited to a maximum of three memory DIMMS - hopefully Corsair is working on a version that allows for the monitoring of 4 memory DIMMs with one unit!
4) Only makes sense to buy this product if you have a clear window on the side panel of your PC or remove the side panel altogether
I do highly recommned this product - go get yourself one now. Keep in mind that if you plan to upgrade to a quad channel memory motherboard (Intel Sandy Bridge-E or Ivy Bridge), you will most likely require two of these for each set of DIMMS which will be physically separated on most of the new motherboards.