7 years is very good for an aluminized system. Now for it to be pristine after 7 years, that has me baffled...
409SS is MUCH better than aluminized steel, in any part of the exhaust (depending on exact location, the life differences can be larger or smaller)
BTW, I'm not ragging on those eyeing the $149 pipe...I'm quite tempted as well. And install is much easier than the headers, so if it rusts out in 3 years, you can just put a new one in.
PS I have an aluminized system on my car. I'll be looking at it yearly and patching the rust spots with Rust Destroyer. I already have some rusty juice coming out the tailpipes, and its been only 1 month...Should have gone stainless...