That is a long commute through 7 years and 7 winters and dark evenings.
If you have the choice (as you do) and can avoid it then personally as a parent that's what I'd do.
SCGS is an excellent school and your dd will have more time to rest and complete homework and revision.
On a personal level I totally agree. I never considered the KE schools because we live in Sutton. I put SCGSG first and our local comp 2nd as I didn't want them travelling. It was very helpful today when DD2 forgot to take her science project to school that my mother in law could just nip in with it! The office were apparently brilliant this morning when she was upset. They found nans number,called her and let DD2 speak to her.
It is also much easier for me to get to after work on parents evenings!!!