This the classic, which is better scheme. I just want to be sure I'm looking at the right stuff before I plop in my CC #. I've got a few choices. Take a gander: Option 1 - Kingston HyperX 4GB (2 x 2GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Option 2 - G.SKILL 4GB (2 x 2GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Option 3 - Crucial 4GB (2 x 2GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Options 2 & 3 cost about the same. $36.49 and $36.99, respectively. Option 1 is $42.99. And is CL 4. Is that going to make a difference? Is there any other differences between the HyperX and the gSkill/Crucial? All these cards are 200-pin DDR2, PC2 5300. That's what my specific model (sig) MBP takes, right? I understand I can't use PC2 6400 even though my FSB is 800 Mhz. Am I going to notice speed boosts? As it is now, I usually don't swap out memory.