Well in the end I decided to go with two clasps which will keep the bracelet from twisting round my wrist - well, that's if I wear it of course!!!
I did wear it for a couple of days and it really really works well. Not sure I like those clasps but as they do stay on the inside of the wrist that's fine by me.
I'm very open to other suggestions if anybody has them. It's an ongoing problem knowing what clasps to use or make that look good and work well for an old git to put on easily. Comments on this problem will be very welcome.