We have a Radian XTSL that my 2-year-old (30ish pounds) rear-faces in. I drive a Honda Odyssey, and the super-latch was loosening on its own, so we don't use it anymore (just use the seatbelt to belt it in). My 4-year-old (5 in a few weeks) is forward-facing in a Safety 1st Complete Air. It rear-faces to 40 pounds.
I actually like the Complete Air better, I think, and I don't think the 5 pounds is all that big of a deal. My average-sized almost-5-year-old only recently reached 40 pounds, and my 6.75-year-old weighs 46 pounds. Even my 2-year-old, who was 28 pounds at 1 year, was only 30 pounds on her 2nd birthday, so a 40 pound RF limit would be fine for us.
I have a 4-week-old who is currently riding in a infant seat (carrier style), and I think we'll likely pick up another Complete Air for her when she outgrows the infant seat.