The definitive OTP ( Off-The-Peg ) List (<£500 and <£1,000 sections)

You can spec any Condor as you please. If you want 'fast', responsive wheels then get some Mavic Open Pros laced to the best hubs you can afford with the lowest spoke count that your weight will allow. I'm 6' 4", 205lbs and use 36 hole and they are still straight and true after a year. If you weigh a lot less then 28 could be ok for you, speak to your wheelbuilder. The trick with light feeling wheels is to keep the rotational mass to a minimum, hence forget the deep section rims like Deep Vs, besides which any aero benefits only come into play at speeds that you will most liklely not regularly hit riding in London. Also you can save weight with latex tubes and the lightest tires you can find, although you may trade off puncture resistance if you can this route.

Do consider your other options though, there is a lot available in the price range of the Pista that is a little more unique. The Pista is a good bike though, don't get me wrong.
I am looking at the Surly as well, and possibly considering BLB. I'm riding a fixed conversion right now, but I ride a road bike a lot in the summer and am looking for a fixed wheel for 'winter training'. The conversion is OK, but a bike with track ends, correct spacing, front and back brake (+hoods), reasonable quality wheels etc would be nice. I know it's a different kind of riding to most people on here, but I thought you'd know most about the OTPs, and I got loads of tips from here when doing my conversion.