It's "the only infant seat that meet industry standards for bassinets" so it can be used for overnight sleep, just like a bassinet. That thing saved my sanity.
We used ours for about 6 months also. It worked great for us... transitioning to the crib took a few days, but I still wouldn't have done it any differently.
We used it almost every day up to 4 months before the transition to the crib, but we didn't put it away until almost 9 months. Any time she had a random cold, etc., she liked to sleep in it for the incline. I wish there was a toddler version.
We love ours. They didn't exist when I had DD#1 and she had horrible reflux. This would have more convenient and secure than propping up her mattress, IMO.
DD#1 11.7.07 - DD#2 11.2.10 (3rd Tri Loss)- DD#3 4.18.12
Re: RNP...
Love the RNP. I wish I had bought it for my first DS. He was a horrible sleeper.