will hks downpipe fit?

i was wondering if the hks downpipe will fit with aftermarket exhaust from a different company. All the places i've checked suggest hks downpipe along with hks exhaust.
The hks downpipe is really inexpensive but is it just as reliable as other downpipes that cost twice as much? Will the coated stainless steel blow out over time or is it just as reliable as any other downpipe?
And finally, will i be able to get away with driving the car around with the catless downpipe or will it smell like ass? If I used my wrx as a daily driver.

well if the downpipe can be used with a factory exhaust it can also work with your aftermarket because the flanges will all be the same, and no the car wont smell, ive had 3 cars now with no "cat" and they didnt smell at all

yeah it will only smell if something is wrong with the car