In my opinion...

You are the right one in this argument... depends on the child... but you can use the type of system that you are talking about for ATLEAST two years... depending on the set up.. maybe 3...

The cost... usually is LESS than if you were to buy each item (car seat, carrier, stroller) seperately... Not to mention... it is most convienient when you have more than one car.. since the car seat itself can most often be used without the "base" in a different vehicle...

Tell your mom.. she is most welcome to buy you all three tho... LOL... you can take them back.. get what you want.. have plenty of money left over for extras

Hugs.. and good luck!!