I have a 2002 GMC Sierra SLE 1500 Extended Cab. I want to get an exhaust for it but im not convinced on which brand to get. I like a loud rumble as well as added horse power and Im in a limbo between purchaseing a BORLA exhaust and a FLOWMASTER. What do you guys think?  

Borla is good, but tends to be expensive. I personally have a Magnaflow on my car, and have been pretty happy with it. But it's hard to beat the sound of a Flowmaster. Gibson also has some nice stuff. Depending on where you live, I'd definitely get stainless. Flowmaster has just recently started offering stainless systems. Heck, I live in California, and I'd go with stainless just for durability and longevity. A lot of the exhaust manufacturers' sites have sound clips. Keep in mind that what you hear from outside the vehicle is different from what you'll hear inside.

Do your buddies have any exhausts on their trucks? What systems do they have? Have they been happy with them? Honestly, word-of-mouth referrals are probably your best bet to get a real-world idea of what it's like to live with an exhaust system.  

I have an 02 Sierra and I have Magnaflow 3" exhaust, it sounds really throaty, If you want a nice deep rumble, when you punch it, its pretty loud!! And I think theirs a power change, If your truck is a 5.3L, Iam not sure about the 4.8L .  

I have a 2005 gmc sierra SLE crewcab. i had the borla and got rid of it for the Gibson stainless sport truck exhaust and am very pleased with the sound. but if you want to be safe go with the flowmaster its always a deep clean sound.  

Flowmaster allll the way it will give you that deep throaty sound if thats what you want. i have one on my 96 4.3 S10 (V6). it sounds sooo good.