Hypothetical Answer:
There are too many other factors to take into consideration.
Out-of-box, shields are generally weak to Thermal damage, strong against Kinetic and Explosive Damage.
Out-of-box, hulls tend to be strong against Thermal and weak against Kinetic and Explosive damage.
So I'd say, start to finish, stripping the shields and then the hull of a ship with either is likely to take just about as long, which is what makes mixed loadouts work so well - thermals for shields, kinetics for hulls.
Not that a pure thermal or pure kinetic can't work, but used together they're more efficient.