Always remember the golden rule.
You get what you pay for. Pay nothing, get nothing.
Also as far as "It boosts HP pretty good". Have you ever put the car on a dyno (before and after)? Does it REALLY boost the horsepower? or does it just feel like it because it's louder? or maybe the clerk at Napa told you it would?
Either way no dyno numbers no truth to it. Just save three times as much, it may take 3 times longer to get that exhaust, but in the long run you'll get something better than say blowing a $100 bucks on some cheapo and then regretting it later.
Good luck
And for crying out loud STAY THE HELL AWAY from the Coffee can exhausts. PLEASE