If you are planning to carry on with Maths to A level, then yes Stats GCSE is definetly worthwhile. I took my general maths gcse in year 10, and my stats in yr 11, so while in my as year i was struggling to remember most of the basic pure maths ( i have a baaaaad memory!) I was well ahead with the stats modules....and was finding them stupidly easy!!!
I did it with OCR and only got a B. But thats bcos I put absolutely no effort into it at all. I would recommend you do revise for it...gives you much higher chance of good grade. I went to every lesson of stats, btu we never did anything...the most eventful lesson was where we lay on the tables eating smarties....hmm i loved stats lessons!
Good luck with it anyway!!!