The main problem with airshocks is all in the installation.
people have been fitting airshocks for years and i bet 99% or even more have been fitted incorrectly. The reason that air shocks are fitted incorrectly is because they are sold as a kit and extra bits are needed.
When air shocks are installed incorrectly, they will dispurse air from one shock to the other when cornering unless they are over inflated. In the kit you will find enough air line to connect the air shocks to one common air valve, here is where the problem lies, a shock can not have a controlled air support if it is not contained with in that one unit. Having the common air valve, air is pushed from one shock to the other shock when cornering because of wieght.
This can be eliminated by having individual air valves per shock as single units, that is two air valves for a pair of shocks. You can controll the amount of air that is needed, but will need an air gauge for equal air pressure when filling.
End of the day it will be your decision which way to go. But remember never over load the air shocks as you can do damage to the cars suspension, as it will act as a solid rear if enough air is pumped in to the shocks themselves.