WARNING! After several attempts, I found that the RAM I had was defective. So, I bought two 8GB Modules through Amazon, specifically dedicated to Macs and now my MacBook Pro Mid 2010 works great with 16GB of RAM.
I solved perfectly with 16 GB of RAM purchased from Amazon. Exactly search with Google: Timetec Hynix IC Apple 16GB Kit (2x8GB) DDR3 PC3-8500 1066MHz memory upgrade for iMac 20 inch /21.5 inch / 24 inch / 27 inch, MacBook Pro 13 inch / 15 inch
This RAM is perfect! Now, if I test the RAM using TechTool Pro or Rember (from kelleycomputing.net site) or using memtest (included in Rember) the Test gives me a fast Clock (all 2-2-2-2 !!!!!!) like the best RAM used by Apple.
Feel free to write to i-Fixit and you will see that they will send you new non-faulty RAM Banks. I have tested it with Memtest at low level (without starting the GUI) and the one purchased is perfect with Timing, even, equal to 2-2-2-2