Looking to purchase a convertible car seat for an upcoming cross-country trip with my 11.5 month old (20 lbs, 30 inches). It needs to be safe (obvi), comfy, and user friendly for a plane as well as an SUV rental car. My daughter currently uses a Britax Advocate CS 70, but I feel it's too big, bulky, and heavy to travel with. Was hoping to purchase a compact, light-weight, affordable, nicely padded and easy to install and haul seat. After our trip, we can use this extra seat in Daddy's 2002 VW Jetta. I really like the Combi Coccoro, but it seems a bit pricey for a travel/secondary seat. My other thought was bringing our Graco Snugride bucket seat, but I think she's simply too big for it now. Any recommendations???