We purchased two of these car seats for or twin boys and we now really regret buying them. They were the only car seats that was able to fit with our stroller (Easywalker - which we love love love!) at the time so we didn't have much choice as compatibility with our stroller was quite important to us.
The good stuff... they are great looking car seats and relatively light (although most car seats get heavy quick once you put a 15lb baby in them). They have great safety ratings and have a very long effective life, they don't expire for 9 years, they longest expiry on the market, which makes it good for future children or for re-selling.
The Bad Stuff... They generally just a pain. The handle is constantly in the way when putting a baby in an out so it has to be moved each time which makes it forever in the opposite position then you need it to be in when your hands are full and the baby is crying! The tension strap for the safety harness has to be tucked up in the seat with the baby because if it isn't it gets in the way of the latch mechanism and prevents the seat from locking into the base properly. The sun visor doesn't go far enough ahead so it can't always be positioned to shade the baby from the sun, and they are a pain to carry as the handle position is awkward.

Overall, it is a safe car seat and my children as as well protected in this seat as in any other but it can be quite inconvenient and annoying. We used a Graco car seat with our first child and didn't now how much we liked it until we started using the Maxi-Cosi. I wouldn't recommend this car seat.