'72 K20 LWB Exhaust System Recommendation

[RaptorSentry]

Any recommendations for an exhaust system for a '72 chevy K20 LWB powered by a 350 SB?

Talking with the only shop that does mandrel bends around my part of the state and they are suggesting the following:

Single Exhaust System
Manifold: 2.5" Ramhorns off a corvette
Tubing: 3" 304 Stainless steel (Mandrel Bent, of course)
Muffler: Magnaflow (I'm not wanting to be obnoxious to the neighbors)
Tip: Double Walled (cannot remember if he said chrome or not)

I'm being told that it should perform equal to or better than a dual exhaust system using 2.25-2.5" tubes with an H or X pipe, plus half the cost of a dual system. Unless I am looking for this to be a show truck headers will not give me anymore performance than the corvette manifold. Since I am not wanting this to be a show truck, but a truck that functions as truck and still looks and performs well, any suggestions? Is this a good setup? Plus other than the 3" tube coming out it will look stock.