Please let me say first that I only have experience with car seats as a grandparent.  When my daughter was a baby they did not have car seats that I am aware of.

 I think Cosco makes one of if not the best car seats I've ever used.  Now you should know that I've never "permanently" installed a car seat base.  I have always used the seatbelts to secure the car seat in.  So I can't say anything about the ease or difficulty in doing this.

 I just know that all of my grandkids have all seemed to be happier when they were in Cosco car seats than any other kind.

 Thank You