Hi all. So as the title says I need some quick advice on an iMac I'm looking at 2nd hand to buy this evening. The Mac is a 21.5 inch model, mid 2011, 500GB HDD, comes with wireless keyboard and track pad. 2.5GHz Intel core i5 with 4GB ram. Running Yosemite also. Seller is asking £320.00. But I may be able to get him down a tenner or two. Can you guys advise on whether or not this is worth it? The iMac would be used mainly for essay writing, internet surfing, the odd film, iTunes. Nothing too strenuous. Any advice is greatly appreciated. Thanks!