I need some info from the experts :)

What are the requirements for a child to use a seat like this one? Weight? Age?

http://www.target.com/gp/detail.html/ref=sc_pfb_r_5_0_1041910/602-7328854-3606222?ie=UTF8&frombrowse=1&asin=B000PB2TMG

Any ones that you would recommend?

We bought that same seat for Ericka. She is 5 years old and weighs 32 lbs. I think she is almost 39 inches tall. That being said, I did not feel very comfortable with her in the seat. She kept sliding herself down in the seat and I did not feel like she was safe enough in it. I switched her back to her Marathon and I'm hoping that will last until she is big enough for me to feel like she is safe in a booster. She is kind of ticked off at me because "all" of her friends have boosters but I like knowing for sure that she is safe.

when they can no longer fit in the 5 point harness comfortably. We moved YDD at 4 because she was too tall for a car seat. Her shoulders would be hunched.

I would say 6 or 7.

Both of my kids use the backless version of this. Cory is going to be 9 sunday. Hes 4'1" and weights 53 pounds so its works out well for him. Lily is 5 1/2. Shes 3'7" (42 inches) and 40 pounds. It works well for her though its not her main carseat.

So I suppose Taylor is waaaay too small for one yet. She'll be 4 in December, but I would guess she only weighs 30 pounds.

as long as she is comfy in her 5 point there is no reason to switch. until she is over the weight limit for the seat/or she is too squished in the harness you can keep her in there. the longer the better.

as long as she is comfy in her 5 point there is no reason to switch. until she is over the weight limit for the seat/or she is too squished in the harness you can keep her in there. the longer the better.

Yea, I planned on keeping her there a while. She's comfy and everything. I was just looking ahead. :)