Well, it all depends what you want to do in the future. If it has nothing to do with maths (ie not an engineering job) then you may be okay so long as you make sure you have enough UCAS points. Maths is one of the most respected subjects though, or so i hear.
I have a friend who wants to be a civic engineer. However he's dropped maths. He's screwed. Think about your future job and if its not maths related then maybe take Use of maths for easy UCAS points? dunno if its recognised though.