I agree, the RNP Sleeper is a great idea! You have the elevation combined with being on their back! But some people recommend a Noggin Nest for their head to avoid flattening if they sleep in it for extended periods of time.
Kristi, Mommy to Josh & Nick (identical twins 6-97) Nathen (3-02), Joey (2-04), Jacob (11-05) & Aaron (12-11) I sell Tupperware!
"A person's a person, no matter how small..." Dr Seuss