Local shop gave me a price of $225 installed for my 03 6 cyl 4Runner. Flowmaster plus custom dual exhaust (exit muffler then out into 2 pipes to the back)

 

that's about the price i paid for mine and i just got single exit. I think that's the best price you can get unless you can install it all yourself. and if you have any second guesses on the flowmaster don't it's worth every penny. IMHO

 

Thats about what I was quoted for flowmasters. How are the 50 series flowmasters on the 4.7?

 

I paid $180 for mine, but I had the entire thing re-piped with one size larger stainless steel pipe. Mine is only single exit though. Doesn't seem like a bad deal for dual exhaust.