Fixed...

Tailwind across the bridge?  Great.  Accidentally hitting the ramp bit?  Bad.  Puncture? Bad.

Got my first taste of puncture changing on the new bike this rather soggy morning.  Not overly arduous but I did end up putting it back on the wrong way but decided to give it a try on the fixed cog side for a run in.

Hmm, that would take a fair getting used to.  Almost got tripped up on a couple of occasions, and just could not work out an elegant dismount.