My km has been built up in almost every combination of:
Alfine, geared, dinglespeed, fixed, singlespeed, flat bar, drop bar, flared drop, riser, road and offroad.
Its had cx tyres on it as a super-muddy singlespeed race bike and it has been ridden over dartmoor with 2.4s front and rear.
Its quick steering and short or long wheelbase thanks to the track ends. It also has that lovely skinny tube lateral flex that makes for a great riding machine. love it to bits.
Get two
Edit: It’s not light but it’s tough enough to take a beating, get thrown in the van and do it again tomorrow. If you want faster just pedal harder :)