Tons of threads on this.
Pretty much you will sacrifice quality for a cheaper header system. Most people that have LCE or DT headers love them. Pacesetters are pretty cheap and never seem to fit right, the paint will be gone in the first five minutes of driving too. It's worth it to get ceramic coating on your header IMO.
As far as mufflers go it all depends on what you want it to sound. I have a flowmaster but it is loud, especially running catless. Although it doesn't sound ricey at all.
No prob. What diameter pipe are you intalling?