I just confirmed that 16GB RAM modules will work in the early 2011 Macbook Pro Models - and in the other Sandy Bridge Models as well, including
* Macbook Pro Early 2011 (13", 15", 17")
* Macbook Pro Late 2011 (13", 15", 17")
Theoretically, other RAM Modules with the same specs should work as well, but I can definitely suggest and confirm the Corsair Modules to work, as they show "Mac Memory" on the German Amazon page and reviewers are reporting successful installs.
Please tell us in the comments section if other RAM modules worked for you. 16GB is currently the largest supported Memory Upgrade for the Unibody Macbook Pro. OWC still sells the same KIT for $239.99.