Speaking of Tubulars, how did your Farsports perform in your CX race? Review?
As to the OP, you will really struggle to get a bad wheel set for £700. As above though, it depends on intended use. If it is for all year round bullet proof light wheels then something from wheelsmiths wouldn't be the worst idea in thew world. I can highly recommend the Ksyrium Elites you mentioned as my brother rides them year round on his Rose Xeon, they are bomb proof and nearly half your budget. I can also recommend somewthing like Fulcrum 1's and Fulcrum zero's for an all year round wheel set. Bomb proof would be my description and a shade under 1500grams these days.
As Vamp says though, if you are racing then get Tubs. For the same money as clincher, they are lighter and offer superior ride quality - IMO.
I am actually someone who doesn't mind using tubs year round on one of my bikes. Just carry a spare tub and/or some sealant. One man once said "life is too short not to ride tubs on a daily basis". As for the "what if you get two punctures argument", well how many cyclists carry two spare tubes for clinchers anyway? With tubs if you tape a spare to the bike and carry a can of sealant you should be set for most eventualities.
If clinchers are your thing though then ignore the last paragraph. Happy shopping.
