I'm not sure which to get! this will work as pretty much my main PC! I've looked at the 17'' benchmarks and they seem slightly higher than the 15''. The 15'' seems slightly more portable whilst the 17'' is obviously a bit more expensive. I really can't decide. I'd like to take it on the train (2x a month) etc. and maybe to university maybe once or twice a month but other than that, i'd be keeping it at home on a desk. I'm obviously looking for a good few years out of the machine too if that factors into anything. Thank you!