So i guess ive decided on getting the base 13 inch model as it is all i require, and im reluctant to spend big on this line, preferring to wait for the new redesign next year before forking out the big bucks as waiting is not an issue. 1) If i expand the RAM to 8GB myself do i void my entire warrantee which im not prepared to do so in that case is it worth paying apple to increase for me or is there little difference for someone who is mainly word processing, surfing the web and listening to music/watching fillms. 2) Where to purchase from ? Now i know my friends before have got great deals from an apple store itself eg free nano with purchase of a mac, if this is not the case is it ok to order online for example if i have a problem will i have to send it back to them onlione or can i take it into a genius bar. Thanks and apologies for my lack of knowledge.