I'd buy a better header. I have Pacesetters and to be honest, they aren't bad (coatng could be significantly beter though), but they came with the car when I bought it.
Personally I like Kooks and will replace mine when I get the funds to do so.
Oh, and yes, no other mid pipes short of a custom job fit the Pacesetter headers so you'll have to buy theirs.
Mods: PaceSh!tter LT's & no cats | Bassani CB | SS OTRCAI | TSP Torquer V3 (231/234 .643/.598) | LS7 Lifters | .650" Springs | Ported LS6 Oil Pump | Monster Stage 2 w/ 18lb flywheel | MGW-P
393/367 at the wheels w/ a slipping clutch (before the Monster S2)
To come: P&P 243's | Fast/TB | Geforce Driveshaft/Axles/Stubs | Suspension goodness