Personally, I've had no problems with OWC's memory matching. As David mentioned, the pins should tell you what motherboards the ram modules will fit into, but the MHz determine which logic boards it may be compatible with. Feel free to check with Other World Computing and make sure they not only fit your motherboard, but are also in the proper speed range for compatibility before ordering the ram modules. Also remember, just because the ram is a larger module (more GB) doesn't mean it's going to be faster (MHz) than the ram that's already in there.
SSS - I think your question wasn't asked so let me ask it for you and answer it:
Can I put more than 8GB of RAM into any of the MacBook Pro systems? The answer is maybe.
Here's a listing of models you can add 16MB to: C-Net article on new MBP memory options.
Now the down side of doing this:
Unless your working on very big data files it won't help you and it will use more power (and add more heat) to run your system shortening the amount of time you have on battery. Lastly, its wicked expensive.
A better option would be to swap out your optical drive for a SSD. Then you'd see a big performance improvement with little up front cost (Vs 16GB of RAM) and it will lengthen your systems battery time.