Install/Impressions Update:
So having the exhaust leak I ran it up to PTunning and they were able to help me out this morning. They tightened up the V-band T-clamp and ended up dropping the header and putting my new gaskets in. I ran into a few snags on the install and overall was a complete pain in the rear. For those who don't have patience, I'd recommend having them installed by a pro. There are a few very tight fitments which make it really hard to tighten bolts.
It still sounds like there is a slight exhaust leak potentially from the V-band. I'm hoping I can get Brady @ Pure Performance to take a look at it when I go up there on Saturday for a local meet.
The car has a good amount of additional torque. It pulls harder as well. It seems to be a fuller acceleration feeling. Overall, about what you would expect out of a header. Pretty happy with the results, but still not 100% and just overly frustrated with it right now...I'll give it a few days.
Also - It's got a little more tone under load but not significant. I'm running the catted version. So for those concerned about noise, it's not an issue. No CEL either.
Quick update: took it out for a spin at lunch and the leak noise seems to have become very slight. Perhaps things will warm up and seal up nice. There is definite improvement in the power band, more torque and it pulls harder up top. I'm running a UniChip tune but thinking with a dyno tune with this header, you might squeak out a few more ponies. It really comes alive on the backroads, you notice it. It isn't enough to say drop everything you're doing and go order a header now. I'm happy with the gains. This car stock has a little trouble stopping and going, now it's very well balanced and the overall performance level is increased. I can keep much faster momentum in/threw/and out of turns.
I can't wait to get the R2s in and the new rubber. I'll be getting the car dynoed next Saturday (@ Performance Autosport in Richmond, VA - DynoJet) and will post the results.