Encouraging replies so far, thanks.
Our biggest worry is the social side of things, we are acutely aware that we will have to enrol them in activities and classes so that they can socialise (especially Alex who is very sociable).
Getting tutors in won't be a problem as we will be saving about 10-12K a year in school fees.
Another thing that prompted the home ed idea was that it will make it easier for us to take them to foreign countries for a month here and there for new experiences.
As for the jump from home ed to secondary school, we expect that they will be fully ready for the change by the time it comes to it.........if not then we can home ed for secondary education as well but I'd prefer to hand that over to the experts at that point because the subject matter will be getting a lot harder.
Nobel prize winners views on school