105 5700 is barely £100 cheaper than 6800, I'd go Ultegra all the way. Though if you were currently running 8/9/10-speed Shimano wheels you'd be looking at a wheel (or at least hub) upgrade to take 11sp.
@Regal started
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105 5700 is barely £100 cheaper than 6800, I'd go Ultegra all the way. Though if you were currently running 8/9/10-speed Shimano wheels you'd be looking at a wheel (or at least hub) upgrade to take 11sp.