/fatherly advice/ If this will be your first Subaru or your first WRX I strongly recommend driving the car stock at least 10,000 miles. It takes time to understand your baby, learn how she leans, learn what she sounds like when shes happy and when shes mad. If your treat her nice for the break in period and learn how it runs then when it comes time to MOD your car make decisions based on what you think it needs, not the same intake and exhaust package the rest of the world is running. /advice/
As far as the reliability of COBB and Invidia parts they are top notch, I've heard very little negative feedback on either of those companies. There have been cases where individuals have had less than stellar results but those are the outliers.
Intake and exhaust will not CAUSE ringland failure but over tuning a stock platform by running super lean or running to much boost on pump fuel will cause issues with any platform.
my recommendation is to drive the car stock until you know it inside and out, then go to a tuner and get a VERY CONSERVATIVE tune with the intake and exhaust of your choice.
Slow is Smooth > Smooth is Fast