Andre, did you install the Crucial 16 GB kit, CT2KIT102464BF160B? I too see the "not-compatible" message on the Crucial site, and the configurator wants you to spend the extra $3-$4 for Crucial # CT3327430, but I see no difference in the specs between these two models. Both are 1.35 v, CAS 11, etc. etc.
I know it's only $4, but is there a reason why I should not get the less expensive CT2KIT102464BF160B?
By the way, the RAM would be going into a base i5 13" MBP.