Did lots of instruction in both, and my observation is that the Cessna is the better trainer if only because the Piper is slightly easier to fly. I had several students transition from one to the other, and the guys who learned in high-wings seemed to have an easier time transitioning to the low-wings than low-wing to high-wing.
I do have to admit, though, if I were buying my own I would lean to the Piper if the $$$ was the same.
There's good and bad with each. Maybe the best idea is to go out in each of them and decide which one you like better.