Hey everyone. I've never owned a MacBook Pro and I ordered one today that should arrive in a few days. It is the basic model and it comes (of course) with 2 GB of memory. I know that Apple charges an irrational amount of money for a little more RAM, so the best choice is to buy it from someone else. I wanna go the right way since I don't want to make a mistake, and so I ask for your help. First of all, is it right that if I change my RAM my guarantee won't work anymore? Second, where should I buy it and are there any specifications that I should take into account? I'd prefer it if it wasn't an online store. I don't live in the States, but I travel a lot there, so I could go to a store, but I wouldn't be able to get the product shipped to an address since I don't have one there. Anyway, thanks for the help. Very much appreciated.