swap is only important if you hold a position for days/weeks and I am that kind of trader.
I noticed there is a vast difference in how much different brokers will charge you, so you really have to look around to minimise costs.
and that`s what I am doing too.
on 100forexbrokers there`s a list of UK brokers and you can also search for swap charged by brokers on other sites....
combine the two and hey presto you have your UK cheap swap broker.
after finding the ideal broker, still do a search at FSA if that broker still holds a license and should be regulated in the UK.