Should I put my daughter into K1 class

hi all,

my daughter is a big girl (born by earlier of the year). In fact, I am considering to put my daughter into nursery class (2years old class) in the coming September this year. But at the time, she will be 2 year and 7 months, she will become the oldest in the nursery class.
According to the advice by one of the international kindergarten, they suggest me to apply their K1 class for my daughter in coming October rather than let her study the nursery class, as they learn from experience the big kid studying in K1 will benefit more than they study in nursery. As they said nursery class will only teach the students how to take care themselves and social skill, but the kids in K1 will learn more knowledge. I am doubt to put my daughter into K1 for coming October, as in this case she become the youngest in the K1 class. I heard alot that better let the kid be the oldest in the class, they will more confident and happy. Is that true? Should I put my daughter into nursery? or let her repeat K1 if necessary?

thank you for all advice in advance!!!

cpmummy