Do I need a c-8 pro vs a c-8 or stick with a c-7?

Will likely be faster. This is fully dependent on the Z-Wave mesh.

If you have any of the more recent Qolsys panels, you can actually reuse it with control from Hubitat using these awesome drivers:

The benefit is that you can reuse your existing sensors tied to the alarm panel. Even if you never arm/disarm it. It's really hard to beat the range and battery life of those RF based sensors.