I Just Bought These - I'm A Bit Shocked

jonaent Are they meant specifically for the track and not for urban road use? i.e. no skidding? Do u think I'll be able to re-use the Record Hubs on different rims?

I believe you can get away riding on the track without a lockring, but you'd have to ask someone who has actually used a track more than once (i.e. not me).

Tubs have many advantages on road and track as velocity boy says, but they are probably not the best choice for urban fixed (more debris on the road for punctures, and can be more expensive to replace if you wear through them quickly from skidding). Up to you though.