hi i was just wondering if anyone could suggest any back carriers which would be ideal to go shopping with mainly and also on walks and days out to places like the zoo. when i go shopping i plan on having dd1 (has sn) in the buggy and dd2 on my back. i've looked at the babyhawk mei tai and the ergo. anyone tried these or got any other suggestions? also where i'm i likely to find them second hand but in a good condition?
TIA