2-3 hours per day! If your child is bright enough, surely this amount of prep isn't required. I'm certainly not planning on doing this much with my son over the Summer holidays. He has a tutor for an hour a week, and I'll probably do a practice paper or two each week with him as well. I think if I gave him 2-3 hours per day he would start to resent it, and it would possibly have a negative rather than positive effect. I believe he is clever enough and capable of passing with the prep I have planned. If he doesn't, then I guess it wasn't meant to be.
And you, my friend, have got absolutely the perfect attitude to ensure that your son will do superbly, wherever he goes!
I completely agree with you - if you are having to do 2-3 hours a day to get your child in, what are you going to do when you get there - do 2-3 hours a day just to help them keep up? 2-3 hours a day in the holidays? My sons wouldn't have agreed to do that much in a week, let alone a day!