I have had this 16GB of memory in my MBP for 7 days now. My MBP has been ran like I typically do for 15 to 16 hours a day all without a single problem. 10's of hours of video has been edited through it, in addition to web surfing, playing music, photoshop, Word, Excel, IM and FTP all without a hitch. I am running a Momentux XT Hybrid drive and since adding this memory I have not really seen any beach balls and defiantly no freezes or lag.