So when my son got to the toddler stage, I was worried about how to keep him warm in his stroller. We live in the city, so travel by stroller is a way of life. He loves to be outside, but really dislikes being covered up - you can see the source of needing this product! Overall, we have found this product to be very good - it is machine washable, it is warm for my son (16 months at the time of purchase), there is room for him to grow into it a bit this winter, it fits our Maclaren Quest stroller nicely, and it is attractive. The only downsides we have noted are that we wish it had one zipper up the middle, instead of having a zipper up each side. The reason for this is that we think it would be tougher for our son to get his hands out of the bag this way - he is nothing short of Houdini-like, however, in his ability to get himself out of outwear and protective items like this bag, so it may not matter at all.
The other thing is that is does not attach to the stroller as securely as we would like - it has a tendency to slide down the front, and eventually, usually on a rainy day, the bottom of the bag drags on the ground a bit. However, going back to the fact that it is washable, this is not a huge complaint either. This may also be a function of the stroller with which you are trying to use this.
I would recommend this product to anyone with a squirmy toddler who loves being outside as much as my son does!