I think it really depends on a lot of things.
Holland Park is huge, and unless your child is one of the chosen few, it's really easy for a student to get lost among the masses. If they are the sort of students who don't really need a school support structure (for example because you can afford to buy in your own, if your DD needs counselling or tutors or advice), then HP might be fine for them.
If they are used to a smaller school, and are looking for something which is a bit more nurturing, then HP really isn't for them - HP don't do pastoral care at all, and their super-strict approach will stress a lot of kids out.
The teachers, for the most part, are great, but they don't really have any power, and a lot of them are very young. The leadership team is the group that matters, and ordinary parents don't really have any easy access to them, so if there's any problems, there's not really a path to resolve anything.
Which exact A-levels is your DD thinking of doing?