I considered these courses for DD but at the end decided against it. Reasons being - a) I wanted DD to rest in summer rather than do any extra work and b) I thought those courses were good for DCs sitting separate Maths and English papers in September ( eg. HBS last year).
This year many schools have their second stage (separate English and MAths papers) in December/January so a third course run by AET (from Sept to Dec - suitable for stage 2) may be more appropriate.
Sorry, not much helpful.
Brilliant reasoning berks_mum, you and dd will be just fine