In reply to mikeyjbs:
Hmm... I'm keen on varis most of the time but find them problematic climbing (and scrambling for that matter.) They're specifically designed to give good vision reading, I.e. looking down at about arms length, and good vision for distance, I.e. >2m through the top part. Sometimes climbing you want good distance vision looking down e.g. to check your last placement, and good near vision looking up, e.g. sussing the next placement or hold.
My current solution is to have a cheapy pair of ready readers to wear climbing - I struggle to read a guidebook with them, and distance vision is not perfect, but as a compromise when climbing they seem to work OK.