All brands have their own problems.
I've heard plenty of stories of NX solenoids getting stuck open, Venom/Zex controllers not working properly, and Edelbrock just plain sucking.
I don't see how Zex is worse than any other brand.
If anything, it has less parts than most kits (less things to malfunction) and has less electronics than many kits (again less to malfunction).
I've had my dry kit for bout 9 months now (20 or so bottles) and I've never had a problem.
With any kit, and nitrous in general, its about taking the necessary precausions & following recommendations of the manufacturer.
