Which RAM to buy for mid 2010 15 Inch Macbook Pro
The brand shouldn't really matter. I have G Skill in mine with no problems. The stock was Samsung. The trouble with that specific model is that it doesn't clock down faster RAM properly thanks to some hardware bug with the Nvidia chipset. It's very important to only use 1066 MHz DDR3 with this model (you can usually get away with faster on other models). I had 1333 MHz RAM for a while and I had kernel panics all over the place.

The actual specifications are here:


  
  Double Data Rate Small Outline Dual Inline Memory Module (DDR3) format
  30mm (1.18 inch)
  2 GB or 4 GB
  204-pin
  PC3-8500 DDR3 1066 MHz type RAM