I love grobag sleeping bags, they are well designed, good quality cotton and zip, and come with a room thermometer and instructions to make sure your baby is always sleeping with the right clothes on. This sleeping bag in particular is great because it has a hole at the back (at legs level), which allows to attach baby in the pram or car seat. Brilliant when baby is sleeping and you need to go, but don't want to wake him/her up.
Bubble print is quite cute too, background is cream (not white), so doesn't look dirty even when baby was a bit sick on it. In fact, I love it so much that I bought 2 so that I always have a clean one. I have been using the 6-18 month one since my baby was 4 month and size was fine.