I did it in 2016. Dropped my chain within 200 metres of the start, spent the rest of the ride trying and failing to get back up to the pack for my age group. Good ride though, and should be rideable fixed or singlespeed as there's not much in the way of hills.
I've entered this sportive for the first time and am going to ride it on my singlespeed. Has anyone done it before? Is anyone doing it this year?