Hi everyone, I'm wondering about two things: - Is it worth it to upgrade from a 2011 13 inch (base) MBA to a same class 2013 MBA? What would I get apart from battery? I use the machine for development purposes mainly. Secondly, - This machine is in pristine condition. Have the box, the books, the lot. Battery is also pretty good. Less than 100 cycles, 90% capacity remaning with Apple care valid until late 2014. How much would this be worth in UK currently? I tried doing my homework and checked lots of offering on eBay but they were not sold (I assume due to being buy-it-now sales). I'd really appreciate your honest input for both. Thanks a lot!