Britax is considered by many to be extremely safe, however I could never justify their price with my budget... Graco ComfortSport is a bit more economical as a choice. Consider how long you are actually going to be using your convertible car seat... Is it possible to leave your infant carrier in the car as a rear-facing seat until one year (esp. if you have Graco SafeSeat Step1 or Chicco KeyFit 30 that go up to 30 pounds), and then purchase a forward-facing seat such as the Graco Nautilus 3-in-1 that will grow the rest of the way with your child? (This would cut your car seat investments down to 2 instead of 4)