Max RAM available in MBA is 4GB, is this really sufficient and with the SSD's is RAM as big an issue ? My girl friend has a 2012 rMBP and 4GB doesn't seem enough in that. With the non-upgradability getting it right first time is essential. Was in Apple store checking out a few things and I noticed the new rMBP's are much lighter and sleeker so that advantage to MBA is reduced. My daughter is due an upgrade (my old 2006 white MB is literally falling apart!). Usage is web, email, streaming movies/tv plus normal student stuff so not hugely taxing. Choice is 8gb/256SSD rMBP (or possibly 4gb/128 SSD rMBP) vs 4gb/256SSD MBA She'll get a student discount so reducing the price differentials.