Like most things,you get what you pay for!The FELT complete would probably be the lightest as it has chromoly top and down tubes(lighter than hi-ten steel)kinda depends a little on how old your daughter is and how serious she is about bmxing!if she just wants a bike to ride around like most kids it doesn't matter so much,but if she actually wants to do tricks or jump it would definitely be better to go for a more expensive and lighter frame.Full chromoly would be better but would up the budget a bit.Are you sure you are not gonna be riding it too??!!
Ok.. a distinct possibility!
She is 10 and only wants a BMX as I have almost finished a 1980's Kuwahara Mini for my 8 year old Son... I left it so long that is too small for her to ride too!
She won't care what it is as long as it is purple.
However... if I am allowed to have a go...