Ds3 is 4.5 yrs old and weighs 52 lbs! He is 45 in. tall! He rides in the regent in our primary vehicle! He now rides in the Graco TB in dh Jeep but I want to either move him to the regent or the Monterey! He only rides in this car about 1-2 times a week for about 20 min. tops! What do you all think?? I am going to purchase a Monterey for DS2 anyway so I think I may try ds3 in it to see how he does. He prefers the harness but he may like the Monterey. A big concern is if he likes the Monterey then he may end up not wanting to ride in the harness anylonger in main car! THis will not be an option for him! ANy suggestions?