Hi, Brittany --
Our daughter would NOT sleep in anything that made her lie flat. She had terrible reflux... still does when she gets worked up, and she's now three. The only thing that gave her comfort and us peace was the amby baby hammock. Check it out... at http://www.ambybaby.com/ (ambybaby dot com, in case they strip out the URL from my post). It was LIFESAVER!! She went from sleeping, at most, 2 hours at a stint, and waking herself and us up because of spitting up to sleeping 8-10 hours solid, the first night!
It is a WONDERFUL device that lets babies sleep on their backs with their heads slightly elevated. It's extremely well ventillated, and in conformance with the latest research on SIDS. Our daughter used it 'til she was 9 months old, and then, reluctantly, we had to transition her to a crib because she was able to climb out of the Amby. We'd like to have never had to use a crib because her sleep was so terrific in the Amby. Once she was in the crib, it took about 4 months for her to adjust to flat sleeping. The Amby was worth its weight in gold to us, and I tell everyone I can about it.
Good luck!
H.