Yeh I'd agree with your sister! I didn't learn anything I didn't already know so depends on how well read up you are on it I suppose.
They basically go through things like your diet now etc, about being pregnant. Then they go through the stages of labour and how to recognise you're in labour and how long to wait to go in (on a first it would be 4 minutes apart, on a second 10 mins). Then they went through the different pain relief available. Bit on BF and formula feeding (this is a private day course I'm talking about) and then how to look after LO, just how to dress them and put them down etc.
MOst of it was all in What To Expect and I'd picked up on here. DH found it interesting though cause he'd read nothing on it
Mothercare do an evening that has a midwife at it and goes through some of it and we found good, but you'll have to sit through an hour of cots, buggys etc that you probably already have.