Further Maths is an excellent A Level that I would highly recommend for any mathematician that enjoys being stretched and challenged. That being said, it is not for the faint-hearted, I would only take this A Level if you have a true passion for maths.
A lot of out-of-college work is required because it is unlikely that you will get everything first time, however it is very rewarding when you finally crack a problem that you have been struggling with.
Doing Further Maths has also helped with my Physics A Level, as there is a lot of cross over between the two. However, if you take Further Maths you will be taking four A Levels. If you are mathematically minded and are planning on taking Further Maths alongside other mathematical/scientific subjects, then this course will be for you.