Toddler pram seat

[Claribel]

I'm trying to avoid getting a double buggy, but my toddler is only semi-reliable at walking. I plan to wear the new baby most of the time, but as an alternative way of getting out and about I like the idea of getting a seat for my toddler so that the baby can be in the pram -- especially if it is going to be a cold winter, the new baby might have a chance of lying flat and being toasty warm.

Reviews are pretty mixed, and I just wondered whether anyone has any first hand experience of using one (what I have in mind is something along the lines of this http://www.kiddicare.com/webapp/wcs/stores/servlet/productdisplay0_10751_-1_9917_10001#ReviewHeader), or even better ... does anyone have one they no longer use and would like to sell on?

Thanks a lot