Video-based home tuition packages - has anyone used them?

[Cfr]

I've been contacted by the Sudent Support Service (through my school - I think they got a donation for every parent who replied) about a video-based home tuition package in English and Maths. Since they have made a 1 and a half hour appointment, with all of us present, I assume it's not cheap. They also said it would need a committment from us to set aside time each week for it. has anyone tried anything like this? Does it work? Three of my children are doing well at school, but two are struggling, and I was wondering whether it would be worth it for them ... I'd welcome any comments anyone has about this.