Do not use the home testing service, Despite the advertising it's operated by an outside contractor and, based on my experience, not very good. They conducted the test in my cramped front room using the contents of a rucksack and billed me £503 for a pair of varifocals. The glasses arrived by post, no visit to fit or check them (apparently they don't do that) and they proved not only useless to use around the house but in some aspects unsafe. When I complained the contractor sent someone who took the glasses away and promised a full refund but have now refused to do that. I used Specsavers in the past with no problems but this service is an expensive disappointment that should be avoided.