Headers Headers Headers !!!

1997 c1500 5.0 V8
extended cab

I have done a lot of searching on here but no one really seems to talk about headers at all. I simply want to know (for those of you out there that have headers installed on your trucks) how they work for you and if you are pleased with them.
Are headers a good idea? I am looking for improved fuel economy, better sound, and also extra power when I need it. (Just to let you know: I currently have a 40 series Flowmaster muffler [single inlet/dual outlet] with two turn-down pipes dumped under the bed in front of the axle)
I also want to stay within the emissions laws (I am a vehicle inspector haha) and make sure my headers will be completely legal and have fittings for EGR and O2 sensors.
Which brands are the best (I know Gibson is good but sorry do you really think I have $600 to drop on some headers?!) I have heard good things about Edelbrock (priced around $270-$300), but I have also seen much cheaper headers (FlowTech and SummitRacing brand for like $170-$225)...are they still good?
What gains can I expect? Will it sound a lot better/louder? How much mpg increase have you experienced with headers? Did you self-install? (I want headers that require no welding/cutting and I could install myself)

Please let me know...maybe this will turn into the thread that people can come to research headers!

well if you get edelbrock shorty headers i think, dont quote me on this, that they bolt right up to the stock exhaust and they have the little emmisions pipe thingies that run along the top that i assume must be egr or something. they are good most likely for top end power whereas long headers are good for low end torque

i have dynomax standard series headers, they have an o2 sensor fitting and the holes for the air box? i dont have one but i was told thats what they are for but i have mine plugged, you can use your stock y-pipe, but using a single muffler and a y pipe kind of defeats the purpose of having headers, i have that set up right now but i plan on buyin another dual outlet muffler to go with the other one i just havnt had the money yet, but these headers are 120 bucks from jegs and they are ceramic coated, i really like them and havnt had any problems with them and best of all they havnt leaked.