Thanks everyone, for your input, and to Annah: that makes perfect sense to me about what you said (the timing of shaving and quality of razor), and I will definately use the advice given in these replies.
However, they won't give me an appointment now until I have started hrt so for now I am going to wax. I'm presenting as male now, but I don't care: the whiskers have got to go and shaving closely isn't good enough for me, they have to be gone.