I posted before how I can't decide whether to purchase a 13" spec'd out MBA or a spec'd out RMBP. Starting next year, I will be traveling A LOT. I need a machine that I can carry with me everywhere. Something that is tough and will not be slow. Vigorous climbing, biking, and just intense sport. -Photography is a must. I'm not some guru photo-editor but I have a pro camera and will load them onto my computer's storage. -I'm a casual gamer. The Sims franchise, BioShock: Infinite, and the new SimCity are what I plan on playing on my down time. -I have at least 5 programs open at once. Usually Safari, iTunes, Microsoft Word, Pages, and Mail are open at one time. I don't want a machine that would lag. (By the way, all my documents are over 80MB) -iTunes is my obsession. I have over 30GB of music, 50GB of movies, and over 60GB of TV shows. I am continuously adding music to my library, and I DO NOT want my music to lag while i'm uploading many photos to my site. I hate external drives (had one before, hated that thing), so I will just have it stored on the computer. + iCloud is amazing for keeping track of everything you purchased, so i'm not worried about it being gone forever. -I just want something lightweight. It is crucial that I am able to carry this device in my hand all day, and document everything I encounter instantly without lag. Spec'd out MBA or spec'd out RMBP? this computer must last for more than 4 years. Thanks.