There is a quite long thread on MacRumors about memory upgrades for 2011 MBPs. Take a look on this page:
https://forums.macrumors.com/threads/1133642/
Conclusion:
1) People noticed kernel panics and other instability issues with CL7 and CL11 RAM. CL9 is 100% stable.
2) I couldn't find any information about CL8 RAM kit stability
(neither on MacRumors, nor in Google; probably because CL8 SO-DIMM RAM is pretty uncommon)
So, let's agree that CL9 is the lowest stable latency in our case
(we will become 100% sure about that only after we get info about CL8 stability)
3) Theoretically, 32GB of 1600MHz CL9 would be the best possible kit you could put inside your MBP.
Unfortunately, it will not become available until 2013-2014.
UPDATED at 15 March 2013
Finally, there is 16 GB of 1600Mhz CL9 RAM. Information taken from my post
at this page!
16GB (2x8GB) 1600MHz CL9 RAM comparison
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| _______________ Model ________________ | Works | tRas _ | __ Voltage | Price in $ |
| Kingston HyperX LoVo KHX16LS9P1K2/16 _ | YES _ | _ 27 _ | _ 1.35/1.5 | ___ 129 __ |
| Kingston HyperX KHX16S9P1K2/16 _______ | YES _ | _ 27 _ | ______ 1.5 | ___ 127 __ |
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