Ok so 47 * 272 = £12,784
35 * 290 = £10,150
Based on the two deals on the table the 3 year deal is considerably better, all things being equal.
An extra £18 a month saves you £2634 and means you change your car for another new BMW in 3 years rather than 4 years time.
If you go in ready to buy, you may even be able to get them down a little more.