We got one of the travel units. I have to say that the base that the carrier locks into in the car is extremely handy. When ever I have to pick up our daughter from the baby sitter I'm worried that I don't get the seat positioned correctly. The base automatically puts the seat in the right position, so my wife only has to plop the seat in the base in her car.

My only complaint about the system is that it's bulky. The stroller part takes up most of the trunk on her car.