I definitely recommend that pattern. The instructions were good, the whole process was easy. I only made the bag bigger than the pattern because the lady mentioned that it was a little small for her 4yo and just right for her 2yo. Since I wanted it for a 3yo and I wanted it to last a little while, I made it about 4cm bigger (if I remember well).
One and a half month after making it, I can say that it is a good one. N. uses it daily and is very happy about it.