Little squirts are awesome. Especially for newborn poo which is like glue. I know plenty of people who have survived perfectly well without a LS, but I don't know anyone who has had one and not thought it was well worth the money.

For rash, like Mel said - liners. Only problem is (and my poor BumGs can testify to this), is that they can slip and slide around, so they are good for light smearings of cream, but if it's a serious bout of teething rash and you seriously have to slather it on, then that's the only time I ever use sposies.