I think working front vanes are a little like the difference between a model aeroplane fitted with ailerons, and one with rudder and elevator control only.
Both work well enough, but the one with aileron control gives you that little bit more subtlety of control at the expense of greater complexity.
On 1:1 subs, forward vanes are used for efficient control of depth when near the surface, once at depth, they become superfluous, and where practicable are either folded against the sides of the hull, as on Gato or S-class boats, or retracted into the hull like many Russian subs e.g. Akula, Typhoon etc.
Sail mounted vanes remain extended for practical reasons- not much room in a sail for retraction, and on a lot of our modern boats the vanes remain extended. Not sure on the reasoning behind that, but it certainly gives these boats a unique appearance.
I would say working forward planes is worth the trouble if you spend a lot of time at periscope depth, or perhaps if you're operating in shallow water, where the more subtle depth control of forward vanes would reap benefits.
There are some boats out there that go the other way and have no rear vane control e.g. Delta submersible, Graupner Shark, HFM Deep Dive VI.