Infant car seat help

[twinkie]

Help! My 8 week-old son is 25 inches long and on the verge of outgrowing his Graco infant seat. (His head is barely an inch from the top). Fortunately we borrowed the seat from a friend so we didn't pay for it. Anyway I would rather purchase another infant seat before moving him up to a convertible seat for convenience purposes. Which seat is better: the baby trend adjustable back or the combi tyro? Or is there another seat with the higher length limit that I am forgetting? We have a LATCH car, but we live in the city so I often ride taxis and therefore need a seat that can be used without the base, both in the car and with the Snap and Go. (We will keep the base permanently installed in my husband's car, so I don't care if the base is heavy.) But I do care if the seat itself is heavy!! The lighter the better!! I live on the 3rd floor and have to haul the car seat and the stroller up and down the stairs every time I want to go somewhere. Also, how are the canopies on both of these seats? Does one have better coverage than the other? Thanks for your help.

[Joolsplus2]

I *think* the Adjustable back is going to be a better choice...darn, I should have actually lifted the Tyro when I was checking it out in the store where i work, to see how heavy it is. Overall, though, I think the Adjustable back is a better choice for you, and cheaper.
The Britax Companion has an even higher height limit (30 inches vs 29), but it weighs a ton.

Julie CPS Tech and mom to 2 in seats
http://www.cpsafety.com/articles/RFAlbum/SarahMA.aspx