My 3.5 year old is very close to outgrowing the car seat installed in my husband's car. That car seat, while safe and well loved, only is usable for kids up to 40 lbs. My son is almost there. I wanted to buy another seat that would last a long time, turn into a booster, be affordable but still keep him harnessed for another few years. I once again began doing research. The car seat/booster that best met my needs was the Gradco Nautilus.
I needed to purchase two seats - one for my husband's car and one for my mother's car. I took advantage of some coupons from Babies R' Us and ended up paying around $140 per seat.
The Graco Nautilus is a 3-in-1 seat. It can only be used forward facing. It can be used as
"Extended 5-point harness for children 20-65lbs.Converts to High-back belt positioning booster for child 30 pounds to 100 poundsConverts to backless booster for child 40 pounds to 100 pounds" (Amazon.com)
The car seat did not come fully assembled but after thoroughly reading the instructions, it was very easy to assemble. It did take a couple of tries to adjust the harness to fit my son. There are 4 harness slots and you do have to re-thread the harness each time you need to adjust it. My son fits very well in this seat and has a lot of room to grow. At 3.5 years old and in the 75th percentile for height, he is only on the 2nd slot. I'm so happy I was able to find a seat that will keep him safely harnessed for years to come.
I cannot really comment about the high back booster or backless booster part of this seat as I won't be using either of those options until my son meets the 65 lb limit on the harness. I will try to update ... in a few years.
Installation was done by a professional who had no issues installing the seat. It looked easy to install and I'm sure, if needed, I will be able to do it on my own.
To clean the seat and remove the seat cover, you would have to uninstall the seat and undo the harness. It would take quite a bit of work to do. The seat is very heavy and would not be very portable. This, however, doesn't pose any issues for our family as it will be staying in my husband's car.
My son is very comfortable in his new seat. He loves the attached cup holder and the "secret" compartments in the arm rest. He had no problems sleeping in this seat.
This is a great seat and will last me until he is able to sit in the car without any booster/seat - around the age of 8-10.