Hi Mary! My DS is 10 and has been on the t:slim since November. Although I wasn’t happy with the cartridge recalls, Tandem handled the situation well and we received our replacements very quickly. The t:slim is very user friendly. My son can do everything by himself (except the changes I feel more comfortable doing 
I think other than switching from tubeless to tubed your daughter will be happy with it. I don’t have any complaints. It doses down to the 1000th of a unit and has many extra helpful features. The only thing it doesn’t do is a square wave bolus that I’ve heard other pumps offer. Other than that it’s been great.
