We bought this product to use for our 15 month old son as we use the seat in the middle of the cars rear seat (we also have a Britax Eclipse) and his legs were beginning to get squashed by the front seats. We thought that this seat would be ideal as it was lower down in the car so his legs werent squashed and it will last right through to when he is old enough to come out of even a simple booster seat (11 years). Although we thought it a bit pricey at £100 we thought that as it would last that long it was well worth the money. Well our opinions soon changed as soon as he fell asleep in the seat. Because it is at such an upright angle he cant relax properly into the seat and be supported by it once asleep. The headrest is great but once he is asleep his head is almost at a forward angle so as soon as you need to slow down or brake, you have to do it so gently or else his head flops forward.
All in all I wouldnt recommend this seat to anyone what wants to use it for a child under the age of about 4 years old.