I did not care for this Britax Boulevard but if my son was younger I might think differently. My son was 4 and weighed 36 lbs and 40 inches tall when I purchased. I went with this model since it was the newest at the time and very highly ranked for safety and also harnessed up to 65 lbs, something I was looking for. Our problem with it was that my had less 2 inches of growing room before he would outgrow it by height and wasn't even close to the weight limit of 65 lbs. The other main issue that the headrest is adjustable and needs to be adjusted with your child, being that he was so tall, his head was less then 6 inches from the ceiling and I did not feel that was safe at all. I tried it in several different cars including a 05 Honda Accord, 99 Sebring and 04 Chevy Tahoe which is a huge SUV. If he wasn't so tall I am sure I would have liked it more.
I did like the side impact head wings alot and was one reason I had bought this. The fabric was soft and plush and the install was pretty easy. I love built in lock off clips. I wish this had been made so the base was not so high or removable. That would have probably solved our problem.
I would definately say try this out before buying with your child and car, assume it will be good for shorter younger kids but watch out when they keep growing. It is something that I don't feel can be utilized even close to the 65 lb harness weight and CANNOT be used as a booster at any point.