Straight raw google estimated numbers:
Hubbard -> Kagel = 15.8 miles and 36 minutes.
McClay -> Kagel = 15.8 miles and 38 minutes.
Hubbard -> Towers = 23.6 miles and 36 minutes.
This doesn't include:
gate hassle
wear & tear on tires
need of high clearance vehicle
erosion of the kagel road
driver skill to drive down the kagel road (gate again)
topes [speed bumps] on McClay

EDIT.