I've been using the Vitamin C serum pretty much daily since I made it in April (is it really that long ago??) and I'm impressed.
The colour of the serum really hasn't changed much, perhaps it has a bit more of a yellow tinge than when I first made it but after six months it really hasn't changed as much as I thought it would. I suppose the fact that it's in a black treatment pump bottle helps.
I'm almost at the end of the first bottle and will need to make more soon. Christmas markets, however, are on the horizon and that will require my time and attention before I can make anything for myself.