I'm upgrading an old Cannondale r700 roadbike to 9x2 speed. It is fitted with its original 105 groupset but it needs new shifters. So far I can see two options. Buy a new set of Shimano Sora 3500 levers or get a second hand set of Ultegra 6500 shifters/brifters (ebay has a pair that are 'as new'/never mounted). Does anyone have any advice on whether a modern but lower end component would be a better choice than a 'vintage' but higher end component?