to answer you guestion a little more in depth-
evo's sti's supras silvias ae86's all have exhaust piping that goes under the rear lca's- in stock form they have a sunch of bends in them that are somewhat restrictive.
so the angled exhaust is straight piped down the middle of the car underneath and is angled so that is ends up in the correct area for the muffler to be placed-
on hondas, the piping goes OVER the rear lca, so if you may have seen- some guys on here with hatches mostly will get a custom exhaust done with piping under the rear lca like all the drift cars, etc.
the hks exhaust for the dc5 is angled more for looks than fuctionality
so if you want a true angled exhaust for function purposes, there you go